Answer:
The change in the area of the rectangle is 0 square feet
Step-by-step explanation:
To solve this problem we have to calculate the area of the two rectangles that give us
first we have to know the formula to calculate the area of a rectangle
a = area
l = length = 12ft
w = width = 5ft
a = l * w
we replace the known walues
a = 12ft * 5ft
a = 60ft²
we do the same with the other rectangle, but first we have to calculate its sides
w = 5ft - (5ft * 20/100)
w = 5ft - 1ft
w = 4ft
l = 12ft + (12ft * 25/100)
l = 12ft + 3ft
l = 15ft
a2 = 15ft * 4ft
a2 = 60ft²
to calculate the change in the area we subtract (a - a2)
a - a2 =
60ft² - 60ft² = 0ft²
Answer: b. 125
Step-by-step explanation:
Find the square roots of each, and if the square root is a decimal, it is not a perfect square.
Square root of 81: 9
Square root of 49: 7
Square root of 100: 10
That leaves 125.
Answer:
x = 21
Step-by-step explanation:
You can solve this problem by using similar triangles. You can tell that the two triangles are similar by AAA (since two angles are the same, the third must be too).
Now that we've established that the triangles are similar, you need to identify the corresponding sides:
12 corresponds to 28
9 corresponds to x
In order to find x, you'll need to find the scale factor, which you can find by dividing 28 by 12:
28 ÷ 12 = 7/3
Now that you know that 7/3 is the scale factor, you can multiply it by 9 to find x:
9 × 7/3 = x
x = 63/3
x = 21
X(x - 2) = 4 [upon multiplying and moving the 4 becomes x² - 2x - 4 = 0] x(2x + 3) = 12 [upon multiplying and moving the 12 becomes 2x² - 3x - 12 = 0] 3x(x + 8) = -2 [upon multiplying and moving the -2 becomes 3x² + 24x + 2 = 0]