If you want to solve this problem using formulas, there are two important formulas:
t1 = first term = -5
tn = nth term = last term = -5
n = numbr of terms
Sn = sum of the n terms
tn = t1 + (n - 1)d ---> 65 = -5 + (n - 1)(5)
65 = -5 + 5n - 5
65 = -10 + 5n
75 = 5n
n = 15
Sn = n(t1 + tn)/2 ---> Sn = 15(-5 + 65)/2
Sn = 450
So ur answer rounds up to 450
Letter c
:)
hope i helped
~Luis
Answer:
see below
Step-by-step explanation: 5 23 8 03
the lenght of the longer leg of a right triangle is 9 ft longer than the lenght of the shorter leg x. The hypotenuse is 9 ft shorter than twice the lenght of the shorter leg.
shorter leg = x
longer leg = x + 9
hypotenuse = 2x - 9
Pythagorean theorem = a² + b² = c²
shorter-leg² + longer-leg² = hypotenuse²
x² + (x+9)² = (2x - 9)² solve for x
x² + (x+9) (x+9) = (2x - 9)(2x - 9)
x² + (x²+18x+81) = (4x² - 36x + 81)
(2x²+18x+81) = (4x² - 36x + 81)
0 = 2x² -54x
0 = x(2x - 54)
0 = x and 0 = 2x -54
54 = 2x
27 = x
shorter leg = 27
longer leg = 36
hypotenuse = 45
divided all the values by 9 and you get a 3, 4, 5 right triangle, so the answer checks correct
Answer:
AR is 3 using Pythagoras 5^2 - 4^2 = 3^2. sin R is just sin (AC/RC). cos is adjacent over hypoteneus. tan is oppositve over adjacent. and sec is 1/cos, csc is 1/sin, and cot is 1/tan.