y=2x
4y+2x=150
2007-03-16 08:06:32 · 4 answers · asked by ..... 4 in Education & Reference ➔ Homework Help
x is either 8, 21, 10, or 15
2007-03-16 08:09:25 · update #1
Let me guess, "The Idiot Test 3"?
You asked for an answer, and here it is. -And since you didn't request it, it's without an explanation.
The answer is 15.
2007-03-18 07:27:25 · answer #1 · answered by AlienPoison51 2 · 0⤊ 0⤋
y=2x
4y+2x=150
That is a system of equations. Since you already have y equal to something (2x in the first equation), go ahead and put 2x in the place of y in the second equation. They are the same after all...
4(2x) + 2x = 150
Distribute into the parenthesis.
8x + 2x = 150
Combine like terms.
10x = 150
Divide both sides by 10.
x = 15
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If you want to solve for y...
Since x equals 15, put it into one of your equations to get y. The first one would be easier, so just use that one.
y = 2x
Substitute 15 for x.
y = 2(15)
Multiply.
y = 30
So, x = 15 and y = 30. This is how you write your answer:
{15,30}
2007-03-16 08:46:40 · answer #2 · answered by ♥pirate♥ 4 · 0⤊ 0⤋
substitution (put the 2x in where the y is in the 2nd equation)
4(2x) +2x = 150
8x + 2x = 150
10x = 150
x = 15
2007-03-16 08:09:59 · answer #3 · answered by csucdartgirl 7 · 1⤊ 0⤋
4(2x) + 2x = 150
8x + 2x = 150
10x = 150
x = 15
2007-03-16 08:29:22 · answer #4 · answered by 7 · 0⤊ 0⤋