Question

Solve the system of equations.
3x−4y=40
5x−5y=55 (1 point)
Responses

(8,−3)
left parenthesis 8 comma negative 3 right parenthesis

(18, 7)
left parenthesis 18 comma 7 right parenthesis

(14, 3)
left parenthesis 14 comma 3 right parenthesis

(4,−7)

Answer 1

To solve the system of equations, we can use the method of substitution or elimination. Let's use the method of substitution.

From the first equation, we can solve for x:
3x - 4y = 40
3x = 4y + 40
x = (4y + 40)/3

Now substitute x into the second equation:
5x - 5y = 55
5((4y + 40)/3) - 5y = 55
(20y + 200)/3 - 5y = 55
(20y + 200) - 15y = 165
20y - 15y = 165 - 200
5y = -35
y = -7

Now substitute y back into the first equation to solve for x:
3x - 4(-7) = 40
3x + 28 = 40
3x = 40 - 28
3x = 12
x = 12/3
x = 4

Therefore, the solution to the system of equations is (4, -7).