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Identify the solution:

2x + 3y = 3
y=-2x+9

User Yetiish
by
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1 Answer

6 votes

Answer:

(6, -3) aka x = 6 and y = -3

Explanation:

since you are given y = -2x + 9, you should start by substituting the expression -2x + 9 for y in the equation 2x + 3y = 3.

here's your equation after plugging in the expression that's equal to y:

2x + 3(-2x + 9) = 3

distribute 3 to -2x

2x + 3(-2x + 9) = 3 ⇒ 3 · -2x = -6x

...and to 9.

2x + 3(-2x + 9) = 3 ⇒ 3 · 9 = 27

now you're left with 2x - 6x + 27 = 3.

combine like terms.

2x - 6x + 27 = 3 ⇒ -4x + 27 = 3

subtract 27 from both sides of the equation. since +27 and -27 cancel each other out, you're left with subtracting 27 from 3, which gives you -24.

now your equation is -4x = -24.

divide both sides of the equation by -4.

-24/-4 = 6

...therefore x = 6.

since you have your x value now, you can plug that into the equation for y in order to solve for y.

y = -2x + 9 ⇒ y = -2(6) + 9

multiply -2 and 6.

y = -2(6) + 9 ⇒ y = -12 + 9

add -12 and 9.

y = -12 + 9 ⇒ y = -3

...and now you've solved for y, which is -3.

therefore, your solution is (6, -3), aka x = 6 and y = -3.

hope this helps! have a nice day <3

User Chris Tavares
by
4.0k points