1. -1/20
work: Write all numerators above the least common denominator: -8+2+5/20
*Calculate the sum or difference: -1/20
Vertex coordinates: (h, k)
Vertex form: y = a(x-h)^2 + k
y = 2(x+3) + 2(x+4)
Use distributive property:
y = 2((x+3)+(x+4))
Simplify:
y = 2(2x+7)
y = 4x+14
This is slope - intercept form, not vertex form. Vertex form is for quadratic equations - this is a linear equation.
Answer (in slope - intercept form):
y = 4x+14
A) The first step needs 100 bricks, the second needs 98, the third needs 96, and so on. Therefore the number of bricks for the nth step is: a_n = a_1 + d(n-1), where a_1 = 100 (the first term), d = -2 (difference).
a_n = 100 - 2(n-1) = 102 - 2n, and for the 30th step, a_30 = 102 - 2*30 = 42. So the top step will need 42 bricks.
b) The total staircase will need: 100 + 98 + 96 + ... + 44 + 42, and there are n = 30 terms. Using the formula for the sum of an arithmetic sequence:
S = (a_1 + a_n)*n/2 = (100 + 42)*30/2 = 2130
Therefore, 2130 bricks are required to build the entire staircase.
7a+7b+77
I I hope this helps you