Question

Solve system of equations 1.15x + 0.65y = 8.90, x − 3y = -15

Answer 1

see analysis

Explanation:

1.15X+ 0.6 5Y = 8.90----------(1)

X - 3Y = -15------------------(2)

from equation (2)

X = -15 + 3Y -----------(3)

put equation (3) into one

1.15(-15+3Y)+ 0 .65Y =8.90

-17.25 + 3.45Y +0.65Y = 8.90

4.1 Y = 8.90+17.25

4.1 Y = 26.15

Y = 26.15/4.1

Y = 6.378

put Y= 6.378 into equation (2)

X - 3(6.378) = -15

X - 19.134 = -15

X= -15 + 19.134

X= 4.134