Step-by-step explanation:
so therefore mark jogged 2 36/70km more than his sister
1
Move everything to the left by subtracting 25 from both sides:

Both terms are squares:
is the square of
, while 25 is the square of 5. So, we can apply the factoring

To factor the expression as

A multiplication is zero if and only if one of the factors is zero, so we have

2
The discriminant of the quadratic expression
is defined as

So, you have

3
Similarly, we have

Answer:
B) (0,0); r=5
Step-by-step explanation:
A circle's standard form is (x-h)^2+(y-k)^2=r^2
The center is (h, k) and the radius is r.
So, here the center would be (0, 0) and the radius would be square root 25, or 5.
Answer:
{x,y}={5,-3}
Step-by-step explanation:
(N instead of X for variable)
N x 7 < 21