Algebra

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One-Step Equations:

a + bx = c

Two-Steps Equations:

ax + b = c

Two-Steps Equations:

x ÷ a + b = c

Two-Steps Equations:

a (x+b) = c

Always do opposite

4x = 20

-4 = zero pair so cross out 4

20 ÷ 4 = 5

x = 5

d ÷ -4 = 3

+4 = zero pair so cross out 4

3 x 4 = 12

x = 12

(+) and (-) are always first

(÷) and (x) are always second

1. (show wok)

2g + 4 = -6

-4 zero pair so cross out 4

-6 - 4 = -10

2 ÷ 2 = zero so cross out

-10 ÷ 2 = 5

5 = g

2. (less work)

9 + 5j = 49

49 - 9 = 40

40 ÷ 5 = 8

8 = j

Anything done must be applied to both sides

1. ( positive (x) )

10 = b ÷ -2 - 4

+4 = zero pairs so cross out 4

10 + 4 = 14

-2 x 2 = zero so cross out

14 x -2 = -28

b = -28

1. ( negative (x) )

-x ÷ 3 + 6 = 12

-6 = zero pairs so cross out 6

12 - 6 = 6

-3 x 3 = zero so cross out

6 x 3 = 18

18 = -x

flip the 18 and -x

so now x = -18

1. (divide first) :)

2 (g + 4) = -8

add 2 = zero value so cross out

-8 ÷ 2 = -4

g + 4 = -4

-4 = zero pairs cross out 4

-4 - 4 = -8

g = -8

2. (distributive property first) :(

2 (g + 4) = -8

multiply everything in brackets by 2

2 x x = 0

2 x 3 = 6

-6 = zero pairs so cross out 6

4 - 6 = -2

INCORRECT ANSWER BUT THE CORRECT WORK