how do you solve this problem 3x-y=4 and 5x+7y=5

Question

solve the system by subsitution method

3x-y=4

5x+8y=5

Answer 1

Substitution method

Given first equation 3x - y = 4

Subtract 3x  from each side.

-y = -3x + 4

Multiply each side by negative one.

y = 3x - 4 ---> (1)

Given second equation 5x + 8y = 5 ---> (2)

From (1) substitute the y  value in equation (2).

5x + 8(3x - 4) = 5

5x + 24x - 32 = 5

29x  = 37

x  = 37/29.

Substitute the x  value in (1).

y  = 3x-4

y  = 3(37/29)-4

y  = 111/29 -4

y  = (111-116)/29

y  = -5/29

Solution x  = 37/29 and y  = -5/29.