Answer:
a=
Step-by-step explanation:
As we have 2 of the angles, we can find the third. The measure of the third angle is 45 degrees.
As this is the same measure as the other, that means that the side length will be the same.
Now was have two side lengths of 17 in a right triangle, so we can use the Pythagorean theorem to find a.
Recall that the pythagorean theorem states: 
In this case, a is 17, b is 17, and c is a
Knowing this, we can input our value into this formula and solve for a.

No circumference of a circle is very easy to me
Answer:
{-12,0}
Step-by-step explanation:
first to solve this can collect like terms and add
X² +12x=0
and solve it by factorization method
X² +12x=0
x(x+12)=0
it means x multiplied by x = X² then x multiplied by 12 = 12x
so this means x or (x+12) equals to zero
x=0 and (x+12)=0
x+12=0
x=-12
so the solution set is {-12,0}
but can also be done by formula method
Answer:
Square root of 4 is 2
so 1+
=4
frac{[1+sqrt{2x-1]}^2 }{4}=3
so 1+sqrt{2x-1]}^2=12
so 1+sqrt{2x-1}=V12
sqrt{2x-1}=V12-1
2x-1=(V12-1)^2=12-2V12+1=13-2V12
2x=13+1-2V12
2x=14-2V12
x=7-V12
x=7-2V3
I put an attachment to explain better
Step-by-step explanation: