Question

Solve for X and Y 1. y = 2x

6x + 3y = 12

2. y = -4x + 2
y = 6x - 8

3. y = x - 4
-4x - 6y = -16

4. x = 3y + 1
2x + 4y = 12

Answer 1

Explanation:

1. If y =2x

solve for y in (6x +3y) = 12

6x + 3(2x) = 12, 6x + 6x =12

12x = 12 , x= 1

to find y , from y =2x

y = 2(1) , ( x = 1 and y = 2)

2. y = -4x + 2

y = 6x -8

y = (-4x + 2)(6x-8)

= -4x ( 6x -8) + 2(6x-8)

-24
`x^(2)` + 32x + 2(6x-8)

-24x2 + 44x - 16

3. y = x -4

-4x -6y = -16

-4x - 6(x - 4) = -16

-4x - 6x - 24 = -16

-10x - 24 = -16

-10x = -16 + 24, -10x = -8

x = 0.8 , to get y , we input x value into eqn(y = x-4)

y = 0.8 -4, y = -3.2

x = 0.8, y = -3.2.

4. x = 3y + 1

2x + 4y =12

2(3y + 1) + 4y = 12

6y + 2 + 4y = 12

10y + 2 = 12

10y = 12 -2

10y = 10

y = 1, to get x

x = 3y + 1

x = 3(1) + 1 , x = 4

( x = 4 and y = 1).