Answer:
find the square of both numbers
13²=169
5²=25
minus the square
169-25 to get 144
find the square root of 144
✓144=12 the third side is 12
<h3>
Answer: b = 4 and c = 7.</h3>
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Explanation:
Comparing y = x^2+bx+c to y = ax^2+bx+c, we see that a = 1.
The vertex given is (-2,3). In general, the vertex is (h,k). So h = -2 and k = 3.
Plug those three values into the vertex form below
y = a(x-h)^2 + k
y = 1(x-(-2))^2 + 3
y = (x+2)^2 + 3
Then expand everything out and simplify
y = x^2+4x+4 + 3
y = x^2+4x+7
We see that b = 4 and c = 7.
The
first graph.
The equation is x - 1

3
In order to solve it, you need to get x by itself.
Add 1 to both sides. 3+1=4
x

4
Since this is your sign

the arrow has to point towards the left, and the circle needs to be colored in.
This is only my opinion. I could be wrong.
My guess is:
Somebody else used that book before you, maybe last year or
the year before, and it was somebody who didn't mind writing
in his book.
One day he didn't have time to write down the homework in his
assignment notebook, so he just circled the homework problems
in his textbook.