STEP 1: Multiply second equation by -3.
After multiplying we have the following system:
3x+4y−3x+3y=8=−36
STEP 2: add the two equations together to eliminate x from the system.
7y=−28
STEP 3: find y
<u>y=−4</u>
<u></u>
STEP 4: substitute the value for y into the original equation to solve for x.
3x+4(−4)=8
<u>x=8</u>
<span><span>A cargo plane flew to Moscow and back.
It took six hours longer to go there than it did to come back.
The average speed on the trip there was 152 mph.
The </span></span><span>average speed on the way back was 380 mph.
How many hours did the trip there take?
(x + 6)152 = 380x
228x = 912
x = 4
The trip there took 10 hours.</span>
The answer to your question is $720
