Friday, 5 July 2024

MID-POINT E1


Find a and b if the midpoint of a line from (a, 6) to (8, b) is

(60, 70)

 

Solution

 

x1=a, x2=8, y1=6, y2=b.

 

(60, 70)= (x1 + x2y1 + y2)

                   2             2

 

(60, 70)= (a + 8,  6 + b)

                  2          2

 

Equating equal values of x;

 

60= a + 8

         2      

 

2 x 60= (a + 8)  x 2 1

                2 1     

 

120 = a + 8

 

120-8 = a

 

a = 112.

 

Equating equal values of y;

 

70 = 6 + b

        2

 

2 x 70= (6 + b)  x 2 1  multiplying by 2 both sides.

                2 1     

 

140 = 6 + b

 

140 – 6 = b

 

b = 134

 

Hence a = 112 and b=134

 

TRY THIS……………………..

 

Find e and f if the midpoint of a line from (e, 19) to (13, f) is (10, 20)

 

 


GEOMETRICAL PROGRESSION A3

 

Find the sum of the 1st eight terms of the geometrical progression 4+16+64+…….

 

Solution

 

G1 = 4, r=4, n=8

 

Sn = G1(rn-1)/ r-1

             

 

S8 = 4(48-1)/4-1

             

 

S8 = 4(48-1)/3 

             

 

S8 = 4(262144-1)

             3

 

S8 = 4(262,143)

             3

 

 

S8 = 349,524

            

 

 

Hence the sum of the 1st eight terms is 349,524.

 

TRY THIS……………..

 

 

Find the sum of the 1st eight terms of the geometrical progression 3+12+48+…….


LOGARITHMS H6

 

Evaluate Log10,000,000,000 -  log 0.0001 + log3243

 

Solution

 

= Log10,000,000,000 -  log 0.0001 + log3243

 

= Log101010 -  log10 10-4 + log33-5

 

= 10Log10 -  (-4log 10) + (-5log33)

 

= (10x1) - (-4x1) + (-5x1)

 

= 10 - (-4) + (-5)

 

= 9

 

Hence Log10,000,000,000 +  log 0.0001 + log3243 = 9

 

TRY THIS……………..

 

 

Evaluate Log1,000,000,000  -   log 0.000001 + log39

Friday, 21 June 2024

ARITHMETIC PROGRESSION 1F

 

The 1st term of an A.P. is 10 and the common difference is 58. Find the 16th term.

 

Solution

 

A1= 10, d = 58

 

An = A1 + (n-1)d   [ formula for n terms ]

 

A16 = A1 + (16-1)d

 

A16 = A1 + 15d    [ formula for 16 terms ]

 

A16 = 10 + (16 x 58)

 

A16 = 10 + 928

 

A16 = 938

 

 

Hence the 16th term is 938.

 

TRY THIS……………..

 

 

The 1st term of an A.P. is 23 and the common difference is 58. Find the 22nd term.


FUNCTIONS 3G

 

Given that F(x) = 13x  -  55. Find F(8)

 

Solution

 

F(x) = 13x  - 55

 

F(8) = 13(8)  -  55

 

F(8) = 104  -  55

 

F(8) = 49

 

 

Hence  F(8) = 49

 

TRY THIS……………..

 

Given that F(x) = 55x  -  20. Find F(3)


SETS H21

 

In Ntoma district the number of people who speak Kiswahili or Lingala is 410. 200 of them speak Kiswahili and 320 of them speak Lingala. How many speak both languages?

 

solution

 

In most cases, OR stands for union whereas AND/BOTH, stands for intersection.

 

Let Kiswahili=n(K), Lingala= n(L).

 

n(K)= 200 ,

n(L)= 320,

n(KuL) = 410,

n(KnL)=?

 

 

 

n(KuL) = n(K) + n(L) - n(KnL)

 

 

410  =  200 + 320 – n(KnL)

 

 

410  =  520 – n(KnL)

 

 

n(KnL) =  520 – 410

 

 

n(KnL) =  110

 

Hence n(KnL)=110 answer

 

TRY THIS……………..

In Bibanja district the number of people who speak Spanish or German is 210. 170 of them speak Spanish and 180 of them speak German. How many speak both languages?


SLOPE OR GRADIENT 1E

 

Find the slope of a line which passes through (-15, -2) and (6,-9)

 

Solution

 

x= -15,  y=-2,  x= 6,  y= -9

 

m = y2 –y1

       x2 – x1

 

m =   -9 –(-2)

           6 –(-15)

 

m =   -9 + 2

           6 + 15

 

m =    - 7

           21

 

 

Hence the slope is -7/21

 

TRY THIS……………..

 Find the slope of a line which passes through (-15, -6) and (1,-9)

Tuesday, 18 June 2024

RADICALS 1E


SEE MORE FORM II VIDEOS HERE:

FORM II VIDEOS


 

INEQUALITIES 1E

 

Solve for x if 2x – 1 ≤ x + 50 ≤ 6x.

 

solution

 

2x – 1 ≤ x + 50 and  x + 50 ≤ 6x

 

2x – x ≤ 1+ 50 and  50 ≤ 6x - x

 

x ≤ 51 and  50 ≤ 5x (having divided by 5 both sides)

 

x ≤ 6 and  10 ≤ x

 

 

x ≤ 6 and  x ≥ 10 

 

TRY THIS………………….

 

Solve for x if 2x – 8 ≤ x + 40 ≤ 11x

ARITHMETIC PROGRESSION 1E

 

The first term of an AP is 5 and the last term is 67.If the arithmetic progression consists of 20 terms, calculate the sum of all the terms. 

 

Solution

 

A1 = 5, n=20, An = 67

 

Sn = n(A1 + An)

       2

 

S20 = 20(5 + 67)

         2

 

S20 = 10 x 72

 

 

S20 = 720

 

 

 

Hence the sum of all 20 terms is 720.

 

TRY THIS………………….

 

The first term of an AP is 7 and the last term is 75. If the arithmetic progression consists of 24 terms, calculate the sum of all the terms