
If 2x+y=5, then y=5-2x, so he substituted 5-2x correctly.
x+4x=5x, so he combined like terms correctly.
If 5x-10=10, then 5x=10+10 -> 5x=20, so he subtracted 10 from the right side instead of adding 10 to the right side.
The answer is C.
Here's the correct solution:
Answer:710
Step-by-step explanation:
10 x 10 is 100
100 x 10=1000
71 x 10=710
Find two numbers that will go Into 64.

Hoped I helped. :)
Answer:
The first one 10 units would be the perimenter of the tenth figure.
1. -4x > -16...divide by -4 and change inequality sign
x < -16/-4
x < 4
2. -y/2 < 6 ...multiply both sides by 2
-y < 12 ...multiply both sides by -1 and change inequality sign
y > -12
3. -5a < -20....divide both sides by -5 and change inequality sign
a > -20/-5
a > 4
4. -b/2 > -1....multiply both sides by 2
-b > -2...multiply both sides by -1 and change inequality sign
b < 2
5. -4b < 24....divide both sides by -4 and change inequality sign
b > -24/4
b > - 6
6. -7c < -14....divide both sides by -7 and change inequality sign
c > -14/-7
c > 2
7. -d/3 > -9...multiply both sides by 3
-d > -27...multiply both sides by -1 and change inequality sign
d < 27