The perimeter of a rectangle is given by the following formula: P = 2W + 2L
To solve this formula for W, the goal is to isolate this variable to one side of the equation such that the width of the rectangle (W) can be solved when given its perimeter (P) and length (L).
P = 2W + 2L
subtract 2L from both sides of the equation
P - 2L = 2W + 2L - 2L
P - 2L = 2W
divide both sides of the equation by 2
(P - 2L)/2 = (2W)/2
(P - 2L)/2 = (2/2)W
(P - 2L)/2 = (1)W
(P - 2L)/2 = W
Thus, given that the perimeter (P) of a rectangle is defined by P = 2W + 2L ,
then its width (W) is given by <span>W = (P - 2L)/2</span>
Answer:
B. x < -8 or x > 8
Step-by-step explanation:
You can use process of elimination to solve this problem by going through every solution and testing them out, but let's jump right to B.
Process:
You know that since the inequality states that x^2 has to be greater than 64, x has to be more than 8, or less than -8.
This is because 8^2 = 64, and -8^2 = 64, and the inequality requires the answer to be more than 64.
Looking at B., you can see that if x is < -8, the square of, for example, -9, would be 81. This is greater than 64, so this works!
Now, B. also has an alternative. The 'or' is a major clue to which is the correct answer, since the square root of any number can be positive or negative. (-8^2 = 8^2)
The 'or' states that x must be greater than 8. So, for example, if we take the square of 10, we get 100, and that is also greater than 64.
We've proven that this solution is accurate for both parts, so it is definitely the one we want!
Hope this helps!
To find the original price, you could use a variable to represent the original price in this equation;
Let p represent the original price
.70 × p=11.20
to solve this, we'd isolate the variable (p)
p=11.20 ÷.70
p=16
The original price was $16
Answer:
y = 0.5 (x^2 -2x + 16) has a y-intercept of 8.
Step-by-step explanation:
The x-coordinate of every y-intercept is zero. To determine which of the four quadratics given here has a y-intercept of 8, we need only substitute 0 for x in each; if the result is 8, we've found the desired quadratic.
O y = 0.5(x + 2)(x + 4) becomes y = 0.5(2)(4) = 4 (reject this answer)
O y = 0.5 (x - 2)(x + 8) becomes y = 0.5(-2)(8) = -8 (reject)
O y = 0.5(x2 -2x - 16) becomes y = 0.5(-16) = -8 (reject)
<em>O y = 0.5 (x2 -2x + 16) becomes y = 0.5(16) = 8 This is correct; that '8' represents the y-intercept (0, 8).</em>
Answer: 1, 3, 6
Step-by-step explanation:
