40% of 65
0.40(65) = 26 returned the survey. (assuming that everybody who took the survey returned it.)
3 miles is 4.8 kilometers which divided by 4 is 0.75 miles
Discussion
The discriminate is b^2 - 4*a*c
The general equation for a quadratic is ax^2 + bx + c
In this equation's case
a = 1
b= -5
c = - 3
Solve
(-5)^2 - 4*(1)*(-3)
25 - (-12)
25 + 12
37
Note
Since the discriminate is > 0, the roots are real and different. The roots do exist and there are 2 of them.
Answer:
x = 65
Step-by-step explanation:
Angles are equal because of the vertical angle thm
2x + 15 = 145
2x = 130
x = 65