Question

1. 6(3a+4)=12a
- find a
2. 5(4c-9)=25
- find c
3. 2x²-x-1=0
- find x

Answer 1

a = - 4

c = 7/2

x = 1, -1/2

Explanation:

1) 6(3a+4) = 12a

3a +4 = 2a

a = -4

2) 4c -9 = 5

4c = 14

c = 7/2

3) 2x² - x -1=0

2x² -2x +x -1 =0

2x(x -1)+1(x-1)=0

X = 1 or -1/2