You use the FOIL method, and how you do this is -
(x - 7) (x + 8)
Multiply the first x by both numbers in the second factor. Which means, you multiply x by x and 8, the two in (x + 8).
With this, you get -
x^2 + 8x
Then do the same thing with -7.
-7x - 56
Then combine the two.
x^2 + 8x - 7x - 56
Combine like terms.
x^2 + x - 56
So now, 7 x 8 is 56
And -7 + 8 would be 1. And that is the value of “x” which is b in the form a^2x + bx + c.
Now with this, you take those two numbers and make the factors =
(x + 8) (x - 7)
Then you set these equal to 0.
x + 8 = 0
Subtract the 8 from both sides.
x = -8
————
x - 7 = 0
Add the 7 on both sides.
x = 7
Answer: A
Answer:
b=2A/h
Step-by-step explanation:
First I throw everything else to another side with A by dividing them
(A = b)/2h
then I get
b=2A/h
Answer:
The bird has to fly 7.5 m
Step-by-step explanation:
Please see diagram in attached image.
Notice that there is a right angle triangle that defines the situation, and you know two elements of such triangle;
1) one acute angle (
), and
2) the side opposite to that angle.
What you need to find is the side adjacent to the angle, which is what the bird needs to fly horizontally to be above the fish. We named that "x".
The trig function that relates such triangle elements is the tangent:

which rounded to the nearest tenth is: 7.5 m
Answer:
-2x + 5
Step-by-step explanation: