We have the following equation:
x2 + 4x = - (y2 - 20)
Let's review step by step:
step 1:
x2 + 4x = -y2 + 20
Answer: OK
step 2:
x2 + 4x + 4 = -y2 + 20 - 4
Answer: Wrong
The correct step is:
x2 + 4x - 4 = -y2 + 20 - 4
Or equivalently:
x2 + 4x + 4 = -y2 + 20 + 4
Answer:
he did make an error in his work in step 2
Answer:
The answer is D) 2.2km
Step-by-step explanation:
Lets say W=Wesley, M=Max, and J=Jared.
So your equations are M=2J, 2M=W, and M+J+W=21days(3 weeks)
So substituting M and W into M+J+W=21 gives you 2J+J+2M=21, substitute M again, to get 2J+J+4J=21 so you get 7J=21 so J= 3 days. Using J=3, substitute in to find M, using M=2J, so M=2(3) so M=6 and using that, substitute into 2M=W, so 2(6)=W so W=12. And 12+6+3=21 to check.
I am going to say it is probably ....B....