Answer:
answer is D) 0, -5
Step-by-step explanation:
Answer:
![\huge\boxed{(d+7)(d-7)=d^2-49}](https://tex.z-dn.net/?f=%5Chuge%5Cboxed%7B%28d%2B7%29%28d-7%29%3Dd%5E2-49%7D)
Step-by-step explanation:
![\bold{METHOD\ 1:}\\\\(d+7)(d-7)\qquad|\text{use}\ (a+b)(a-b)=a^2-b^2\\\\=d^2-7^2=d^2-49\\\\\bold{METHOD\ 2:}\\\\(d+7)(d-7)\qquad|\text{use FOIL}\ (a+b)(c+d)=ac+ad+bc+bd\\\\=(d)(d)+(d)(-7)+(7)(d)+(7)(-7)\\\\=d^2-7d+7d-49\qquad|\text{combine like terms}\\\\=d^2+(-7d+7d)-49\\\\=d^2-49](https://tex.z-dn.net/?f=%5Cbold%7BMETHOD%5C%201%3A%7D%5C%5C%5C%5C%28d%2B7%29%28d-7%29%5Cqquad%7C%5Ctext%7Buse%7D%5C%20%28a%2Bb%29%28a-b%29%3Da%5E2-b%5E2%5C%5C%5C%5C%3Dd%5E2-7%5E2%3Dd%5E2-49%5C%5C%5C%5C%5Cbold%7BMETHOD%5C%202%3A%7D%5C%5C%5C%5C%28d%2B7%29%28d-7%29%5Cqquad%7C%5Ctext%7Buse%20FOIL%7D%5C%20%28a%2Bb%29%28c%2Bd%29%3Dac%2Bad%2Bbc%2Bbd%5C%5C%5C%5C%3D%28d%29%28d%29%2B%28d%29%28-7%29%2B%287%29%28d%29%2B%287%29%28-7%29%5C%5C%5C%5C%3Dd%5E2-7d%2B7d-49%5Cqquad%7C%5Ctext%7Bcombine%20like%20terms%7D%5C%5C%5C%5C%3Dd%5E2%2B%28-7d%2B7d%29-49%5C%5C%5C%5C%3Dd%5E2-49)
Answer:
Actually that's incorrect
Step-by-step explanation:
Answer:
800 miles
Step-by-step explanation:
Let the number of miles be represented by x
Company A for $110 a day plus $0.80 per mile.
$110 + $0.80 × x
110 + 0.80x
Company B charges $30 a day plus $0.90 per mile to rent the same truck.
$30 + $0.90 × x
30 + 0.90x
110 + 0.80x = 30 + 0.90x
110 - 30 = 0.90x - 0.80x
80 = 0.1x
x = 80/0.1
x = 800 miles
800 miles driven per day makes the rental cost for Company A a better deal than Company B's
Answer:
Option D
Step-by-step explanation:
The questions which involve calculating the angles and the sides of a triangle either require the sine rule or the cosine rule. In this question, the two sides that are given are adjacent to each other and the given angle is the included angle. This means that the angle is formed by the intersection of the two lines. Therefore, cosine rule will be used to calculate the length of b. The cosine rule is:
b^2 = a^2 + c^2 - 2*a*c*cos(B).
The question specifies that a=42, B=120°, and c=35. Plugging in the values:
b^2 = 42^2 + 35^2 - 2(42)(35)*cos(120°).
Simplifying gives:
b^2 = 4459.
Taking square root on the both sides gives b = 66.78 (rounded to the two decimal places).
This means that the length of the third side is 66.78 units!!!