x² + bx - 81
there are 2 formula that fit this equation :
>> x² - a² = (x+a)(x-a)
or
>> x² + 2ax² + a² = (x+a)(x+a)
because the last value of our equation is negative value therefore we have to use the first formula >> x² - a² = (x+a)(x-a)
step:
x² + bx - 81
x² + bx - 9²
because we have to follow the first formula x² - a² therefore bx = 0
x² + bx - 9²
bx = 0
b = 0
40 because you would divide the miles by hours to find the rate of change.
120/3= 40
Maria's dinner bill is $21.89 after tax. If she wants to leave a15% tip, what will the total cost of the dinner be?a. $24.22b. $3.28c. $18.61d. $25.17
Pls answer quick!
7.) Area of a square pyramid is given by A = s^2 + 2sl; where s is the side length of the base and l is the slant height.
Area of given pyramid = 4^2 + (2 x 4 x 7) = 16 + 56 = 72 ft^2
8.) Area of the given pyramid is the area of the hexagonal base plus the area of the six slant triangles.
Area of hexagonal base = (3sqrt(3))/2 x 10^2 = 150 x 1.732 = 259.8
Area of the 6 traingles = 6(1/2 x 10 x 13) = 6 x 65 = 390
Total surface area of the pyramid = 259.8 + 390 = 649.8 ≈ 650 m^2
9.) Using pythagoras rule, the slant height is sqrt(6^2 + 3.5^2) = sqrt(36 + 12.25) = sqrt(48.25) = 6.9 mm
10.) The surface area of a cone is given by πr^2 + πrl
Area = π x 6^2 + π x 6 x 20 = 36π + 120π = 490.1 cm^2
11.) l = sqrt(r^2 + h^2) = sqrt(11^2 + 16^2) = sqrt(121 + 256) = sqrt(377) = 19m
The answer is 5,180! I used a calculator