Use substitution {y-4x=-7 5x+y=-6

y - 4x = -7 1

5x+y=-6 2

Make y the subject in equation 1

Thus

y = - 7 + 4x

Substitute this into Equation 2

We get

5x - 7 + 4x = - 6

9x = -6 + 7

9x = 1

x = 1/9

Substitute x = 1/9 into equation 1

y = -7 + 4x

y = - 7 + 4(1/9)

y = -7 + 4/9

y = - 59/9

x = 1/9 , y = -59/9

Hope this helps

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify