I think you're missing a bit of the question. If her savings can be modeled by x...?
To solve this, I used guess and check.
I started by finding 60²=3600 and 70²=4900. 70² is too much, so I then did 65²=4,225.
After 65², I did 62²=3,844. I knew that was pretty close, so I did 64. 64²=4,096 and 63²=3,969. So, 64² was it.
4,096-4015=81
So, you would need to add 81 to 4015 in order to receive a perfect square, which is 64²(4,096).
I believe the 4th one
an=145+an-1 and a1=20
Nor sure what you're doing on the bottom but use point slope thing
y-0=-2(x+2)
y=-2x+2
So not sure what you're asking but...
yeah, you're right.
6-3/4x+1/3=1/2x+5
6+1/3-5=1/2x+3/4x
4/3=5/4x
x=16/15
