Answer:
-13
Step-by-step explanation:
2x²+26x+156=0
x²+13x+78=0
x²+13x=-78
x²+13x+169/4=-143/4
(x+13/2)²=-143/4
x+13/2=(i√143)/2 or x+13/2=-(i√143)/2
x=(i√143)/2-13/2 or x=-(i√143)/2-13/2
(i√143)/2-13/2+(-(i√143)/2)-13/2=(i√143-13-i√143-13)/2=-26/2=-13
Answer:
1 and -4
Step-by-step explanation:
cause when you factor the equation its (x-1)(x+4)
Answer:
The diameter of a circle with an area of 100 square miles is 20/√π miles.
Step-by-step explanation:
Area =100 = πr^2.
diameter = d = 2r.
100 = πr^2.
100/π = r^2.
√(100/π) = r.
10/√π = r.
d = 2r.
d = 2 * 10/√π.
d = 20/√π
#4 a reflection across the x-axis is the only correct answer , the other ones aren’t correct .
