Answer:
78
Step-by-step explanation:
40 x 76 is the equation by 4x4 of 86 and the 36
Hi there!
When we have an equation standard form...

...the formula of the discriminant is
D = b^2 - 4ac
When
D > 0 we have two real solutions
D = 0 we have one real solutions
D < 0 we don't have real solutions
1.) Find the value of the discriminant and the the number of real solutions of
x^2-8x+7=0
Plug in the values from the equation into the formula of the discriminant

D > 0 and therefore we have two real solutions.
2.) Find the value of the discriminant and the number of real solutions of
2x^2+4x+2=0
Again, plug in the values from the equation into the formula of the discriminant.

D = 0 and therefore we have one real solution.
~ Hope this helps you.
SOLUTION
Write out the equation

To solve this system of equation, the aprropriate method will be substitution
Substitute the expression for y into the second equation for y, we have

Expand the paranthesis we have

Divide both sides by 4, we have

Since the value of x has been obtained, we substitute into the first equation

Therefore
x = -3, y= -4
We know that
[the length of a circumference]=2*pi*r
for r= 4 units
[the length of a circumference]=2*pi*4--------------> 25.12 units
if a full circle (360°) has a length---------------------> 25.12 units
arc for an angle of 72 °---------------------------> X
X=72*25.12/360------------> 5.024 units
the answer is
<span>the length of the subtending arc for an angle of 72</span>° is 5.024 units