Grade 8 Revision

Expressions/Proportions

100

x - x(x - y) - lxl  ; use x = -3, and y = 2

-21

200

p ÷ 3 - (q ÷ 5 - ( p + p)); use p = 3, and q = -5

8

300

r + 3 - (q + r ÷ 6 + q); use q = 3, and r = 6

2

400

Proportion a) n+2/5 = n/2

n=4/3 = 1 1/3

500

Proportion b) 3/4 = x+1/6x

x = 2/7

Equations

100

4(1 - 2v) + 2(5v - 8) = -3v - v

v = 2

200

-22 + 8n = -2(-5n + 3)

n = -8

300

l-4 + vl + 1 = 4

v= {7,1}

400

2 l-2 + ml - 10 = 0

m = {-3, 7}

500

8 + 3 l-10al = 38

a = {-1, 1}

Mix

100

–7d + 8 = –7 + 1 – 9d

d = -7

200

–7 – 5w – 7w = 5 – 9w

w = -4

300

16 = 2 l9yl

y = {8/9, -8/9}

400

8 + 3 ln - 1l < 32

-7 < n < 8

500

x+7/10 = x/6

x = 10.5 

Inequalities

100

6 ly + 1l - 2 > 10

y < -3 or y>1

200

2|5u – 9| > 12

v < 3/5  or  v > 3

300

 4 >= f-6/3 >= -4

-6 < = f <= 18

400

1 + 4m + 4 < -23

m<-7

500

-3 <= -4 - 5 p + 5 p

No Solution

Inequalities 2

100

-5(3 + 7x) - 3 > 192

x <-6

200

8(r + 8) - 6 < -2 - 7r

r < -4

300

-2r < -16 or r + 9 < 14

r>8 or r<5

400

-30 < -3x - 3 <= -18

5<= x < 9

500

-9m - 10 <= 8 and 10 - 3m >= 10

-2 <= m <=0