The answer would be B $4.29
Answer:
2(- 64f + 21)
Step-by-step explanation:
Using the power rule for differentiation, the first derivative of
is
and the second derivative is
which makes E the correct choice.
Answer:
12 < x < 16
What we know:
- The longest side of the triangle is 20, another side length is 'x + 4'
- Since the triangle is acute, we know that the value of 'x' will have to be <u>greater than its right triangle value</u> because whatever 'x' equals will result in a <em>right </em>triangle, not an acute one
- We must solve for the <em>right </em>triangle first in order to determine the acute triangle
Solving for 'x' in the right triangle:
- a^2 + b^2 = c^2
- (x+4)^2 + x^2 = 20^2
- x^2 + x^2 + 8x + 16 = 400
- 2x^2 + 8x - 384 = 0
- simplify x^2 + 4x - 192 = 0
- factor (x + 16) (x - 12) = 0
- solve for each 'x' x + 16 = 0 & x - 12 = 0
- x = -16 & x = 12
- check the value of 'x' cannot be negative, so it is not -16. this means the value of 'x' is 12
- the value of 12 for 'x' makes a <em>right triangle, </em>so that is not the answer. this means the the value of 'x' needs to be <em>greater</em> than 12
<u>Checking your answer:</u>
- original equation (x + 4)^2 + x^2 = 20^2
- with answer (12 + 4)^2 + (12)^2 = 20^2
- (16)^2 + (12)^2 = 20^2
- 256 + 144 = 400
- 400 = 400 this is true, so the answer of 'x = 12' is <em>correct </em>for making it into a <em>right triangle</em>
<em></em>
Solving for 'x' in the acute triangle:
- x = 12 makes a right triangle
- x > 12 minimum for an acute triangle
- what is the maximum value for 'x' in the acute triangle? take the two other side lengths --> (x + 4) < 20 (longest side, so it will be the greater number)
- simplify x < 16
- x < 16 maximum for an acute triangle
Conclusion:
- if 'x = 12' makes a right triangle, then 'x > 12' and 'x < 16' are the values that will make it acute
- answer 12 < x < 16
Answer:
It’s a negative integer
Step-by-step explanation:
