(3 x 7) + (x+40) 7/2x-5) = 180 find x
2 answers:
You might be interested in
Answer:
Dimensions of the rug = 13 ft × 26 ft
Step-by-step explanation:
Dimensions of the room = 21 ft × 34 ft
Area of the room = 21 × 34 = 714 ft²
Cynthia wants to leave a uniform strip of floor around the rug.
Let the width of the rug = x ft
Then the dimensions of the rug will be = (21- 2x)ft × (34 - 2x)ft
Area of the rug = (21 - 2x)×(34 - 2x) square feet
338 = (21 - 2x)×(34 - 2x)
338 = 714 - 68x - 42x + 4x²
4x² - 110x + 714 - 338 = 0
4x² - 110x + 376 = 0
2x² - 55x + 188 = 0
2x² - 47x - 8x + 188 = 0
x(2x - 47) - 8(x - 47) = 0
(x - 4)(2x - 47) = 0
x = 4,
For x = 23.5 area of the rug will be negative.
Therefore, x = 4 ft will be the width of the rug.
Dimensions of the rug will be 13 ft × 26 ft.
Answer:
B) 8 and 24.
Step-by-step explanation:
Just by looking at the answer choices, since one number must be three times the other, we can determine that the correct answer is B.
Regardless, let's work this out mathematically. Let the first number be <em>a</em> and the second number be <em>b</em>.
Their difference is 16. Hence:
The first number is three times the second number. So:
Substitute:
Solve for <em>b</em>. Subtract:
And divide both sides by two:
So, the second number is 8.
And since the first number is three times the second, the first number is 24.
Our answer is B as expected.