Question

-1.5x+0.3y=1.5 1.8x+0.9y=-8.1

Answer 1

X = -2 and y = -5

Explanation: Solve by using the process of elimination. 

Step: Solve−1.5x+0.3y=1.5
Solving for x = −1.5x+0.3y+−0.3y=1.5+−0.3y *Add -0.3y to both sides*

−1.5x=−0.3y+1.5

−1.5x−1.5=−0.3y+1.5−1.5 *Divide both sides by -1.5*

x=0.2y−1
Step: Substitute 0.2y−1 for x in 1.8x+0.9y=−8.1:

1.8x+0.9y=−8.1

1.8(0.2y−1)+0.9y=−8.1

1.26y−1.8=−8.1 *Simplify both sides of the equation*

1.26y−1.8+1.8=−8.1+1.8(Add 1.8 to both sides)

1.26y=−6.3

1.26y1.26=−6.31.26 *Divide both sides by 1.26*

y=−5

Step: Substitute −5 for yi n x=0.2y−1:

x=0.2y−1

x=(0.2)(−5)−1

x=−2 *Simplify both sides of the equation*