Take the second equation and flip it around so the y on the left ends up on the right and the 4x on the right ends up on the left. This makes all negatives positive and all positives negative. -4x + 12 = y
Then add the first equation to the second equation
4x +12 = -7y
<u>-4x + 12 </u>=<u> y </u> this eliminates the x's
<u>24</u> = -<u> 6y</u> then divide by - 6
- 6 - 6
- 4 = y<u>
</u>So if you know that y = negative 4, you can substitute into either equation. I pick the second one because I am a lazy person.
-y + 12 = 4 x
-(-4) + 12 = 4 x combine your numbers<u>
</u> <u> 16 </u> = <u>4 x </u> then divide by 4<u>
</u> 4 = x
So your solution is: x = 4 and y = -4 or this is also written (4, -4)
Does that work for you?
Do cross multiplication.
Convert ounce to pound.
8 ounce is 0.5 lbs
x/0.5 = 17.95/1
x=8.975
Miss Lawrence spent about $8.98
There's an app called photomath that would be useful for these kinds of problems!
If Eli cut both pieces into 4th's, in all they would have 8 4th's.
Because 4 + 4 + 8 :)
x=2
sorry for the bad handwriting btw.