Answer:
No mistake
Step-by-step explanation:
2x + y = 5
x - 2y = 10
y = 5 - 2x
x - 2(5 - 2x) = 10
x - 10 + 4x = 10
5x - 10 = 10
5x = 20
x = 4
2(4) + y = 5
y = -3
She made no mistake
You can check by plugging in x = 4 and y = -3 into the original equations . They fit exactly.
Answer:
Step-by-step explanation:
If we're solving for x then x=12
<span><span>∑<span>i=2</span><span>i=10</span></span>(4+2n)=</span><span>
You can do it by hand, w/o much work .
plug in n=2 into (4+2n)
then plug in n=3 into (4+2n)
then plug in n=4 into (4+2n)
etc until you get to n=10. Add them all up.
</span><span>add 8 + 10 + 12 + 14 + 16 + 18 + 20 + 22 + 24
</span><span>144 jumps!</span>
