Solve using substitution y=3x-5 2x+5y=-42

Mathematics

1 answer:

Paul [167]3 years ago

6 0

Answer:

Solution point is (-1,-9)

Step-by-step explanation:

Put the value of y in the first equation into the second equation.

2x + 5(3x - 5) = - 42 Remove the brackets on the left
2x + 15x - 25 = - 42 Combine like terms on the left
17x - 25 = - 42 Add 25 to both sides
17x - 25 + 25 = - 42 + 25 Do the addition
17x = - 17 Divide by 17
17x/17 = -17/17 Do the division
x = - 1

=======

Solve for y

y = 3x - 6
x = -1
y = 3(-1) - 6
y = -3 - 6
y = - 9

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Two angles are supplementary. The larger angle is 15 more than 10 times the smaller angle. FInd the measure of each angle.

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