Question

Solve the following simultaneous equations 2x+5y=0 and 3x-4y=23

Answer 1

Answer:

x = 5, y = -2

Step-by-step explanation:

2x + 5y = 0 --- Equation 1

Equation 1×3: 6x + 15y = 0 --- Equation 2

3x - 4y = 23 --- Equation 3

Equation 3×2: 6x - 8y = 46 --- Equation 3

We will be eliminating 6x from Equation 2.

Equation 3-2: 6x - 8y - 6x - 15y = 46-0

-23y = 46

y = 46 ÷ -23

y = -2

Substitute y = -2 into Equation 1:

2x + 5y = 0

2x + 5(-2) = 0

2x + (-10) = 0

2x - 10 = 0

2x = 10

x = 10 ÷ 2

x = 5