Write 1080 as a product of prime factors.
Solution
|
2 |
1080 |
|
2 |
540 |
|
2 |
270 |
|
3 |
135 |
|
3 |
45 |
|
3 |
15 |
|
5 |
5 |
|
1 |
Then, 540 = 2 x 2
x 2 x 3 x 3 x 3 x 5
Hence 1080 =23 x 33 x 5.
TRY THIS........
Write
840 as a product of prime factors.
x is inversely proportional to y. x=18 while y=5. Find y when x is 30.
Solution
x
⍺ k
y
x
= k
y
18
= k
5
k
= 18 x 5
k
= 90
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
k
= 90, y= ?, x = 30.
x
= k
y
30
= 90
y
y
x 30 = 90 x y (multiply by y on both
sides)
y
30y = 90
30
30
Hence y = 3 .
TRY THIS…………….
x
is inversely proportional to y. x=120 while y=4. Find y when x is 10.
If Logax = 0.9, find Loga(1/x3)
Solution
= Loga(1/x3)
= Logax-3
= -3 x Logax
= -3 x 0.9
= -2.7
TRY THIS………..
If Logaw= 1.2,
find Loga(1/w4)
Find the slope of a line
which passes through (-1, -8) and (16,-9)
Solution
x1 = -1,
y1 =-8, x2 = 16, y2 = -9
m = y2 –y1
x2 –
x1
m = -9
–(-8)
16 –(-1)
m = -9 + 8
16 + 1
m = -
1
17
Hence the slope is -1/17
TRY
THIS………………………
Find the slope of a line
which passes through (-1, -2) and (9,-12)
A regular polygon has 42 sides. Find the total degrees of
that polygon.
Solution
n = 42
Total degrees = (n - 2)1800
=
(42 – 2)1800
=
40 x 1800
=
72000
Total degrees = 72000
TRY THIS……………………….
A regular polygon has 33 sides. Find the total angles of
that polygon.
Find the midpoint of a line from (33,
12) to (5, 20)
Solution
x1=33,
x2=5, y1=12,y2=20.
Mid point = (x1 + x2, y1 +
y2)
2 2
Mid point = (33 + 5, 12
+ 20)
2 2
Mid point = (38, 32)
2 2
Hence
midpoint = (19, 16)
TRY THIS……………………..
Find the midpoint of a line from (-9,
24) to (9, -4)
