Solve the system
-4x+8y=20
2x+2y=-30

x = -13 and y = -4

Step-by-step explanation:

-4x + 8y = 20 eqn 1

2x + 2y = -30 eqn 2

Step 1: Multiply eqn 1 by 2 and eqn 2 by 4

(-4x + 8y = 20) × 2

(2x + 2y = -30) × 4

we will have

-8x + 16y = 40 eqn 3

8x + 4y = - 120 eqn 4

Step 2: Add eqn 3 and 4 together

20y = - 80

Step 3: divide all through by 20

y = -80/20

y = -4

Step 4: Substitute -4 for y in eqn 1

-4x + 8(-4) = 20

-4x - 32 = 20

-4x = 20 + 32

-4x = 52

Step 5: Divide both sides by -4

x = 52/-4

x = -13

{3 + i, 3 - i, 3, -1}

step-by-step explanation:

it would take 7/10 of an hour too fill the pool.

step-by-step explanation: