Answer:
15
Step-by-step explanation:
Substitute a and b then
Follow PEMDAS
Hope this helps! :)
Answer:
The answer is C
Step-by-step explanation:
Took the test!
a = 4, b = -21, c = -18
to keep from getting "mixed up", evaluate the discriminant first ...
b<sup>2</sup> - 4ac = (-21)<sup>2</sup> - 4(4)(-18) = 729
sqrt(729) = 27
x = (21 +/- 27)/8
x = -3/4, x = 6
since the discriminant is a perfect square, the original quadratic will factor ...
4x<sup>2</sup> - 21x - 18 = 0
(4x + 3)(x - 6) = 0
x = -3/4, x = 6
6+2(x+8)+3x+11+x
First you have to expand the brackets:
6+2x+16+3x+11+x
Now you group like terms (terms with the same or no variable):
2x+3x+x+11+16+6
And finally, combine like terms:
6x+33
Hope this helps :)
Answer:
20.833 feet
Step-by-step explanation:
The light reflects off the mirror at the same angle that it hits it at. So the triangle formed by the beam and mirror is similar to the triangle formed by Kevin and the mirror.
Therefore, we can write and solve a proportion.
h / 10 = 6.25 / 3
h = 20.833
The beam is 20.833 feet tall.
