Question

can you check my work
3x−4y=40 5x−5y=55
i think its 4,-7

Answer 1

To check the work, we can solve the given system of equations. Let's solve it step by step:

1) Solve the first equation:

3x - 4y = 40

We can rearrange the equation to solve for x:

3x = 4y + 40
x = (4y + 40) / 3

2) Substitute this expression for x in the second equation:

5x - 5y = 55

5( (4y + 40) / 3 ) - 5y = 55
(20y + 200)/3 - 5y = 55

3) Multiply the entire equation by 3 to get rid of the fraction:

20y + 200 - 15y = 165

Combine like terms:

5y + 200 = 165
5y = 165 - 200
5y = -35
y = -35/5
y = -7

4) Substitute this value of 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

So, the solution to the given system of equations is x = 4 and y = -7.

Hence, your answer of (4, -7) is correct.