Answer:
N=250
Step-by-step explanation:
"twice as many nickels as dimes" means N =2D [eq1]
"collection of nickels and dimes is worth $25" means
5N + 10D = 2500 [eq2]
(To avoid using decimal points, PLZ express everything in cents.)
Substitution (substitute N from eq1 into eq2]:
5(2D) + 10D = 2500
10D + 10D = 2500
20D = 2500
D = 125
N=2D [eq1 again]
N=2(125)
N=250
Check:
Is 5(250) + 10(125) = 2500 ?
1250 + 1250 = 2500 ?
2500 = 2500 ?yes
The correct answer is x= -6 let me know if you want to know how I got that or if you needed to know if it is no solution/ infinite/etc..
Answer:
area= 59.5 perimeter=31.6
Step-by-step explanation:
the area of the square is 49 because 7x7=49 and the area of the triangle is 3x7/2 because it is half of a rectangle so it is 10.5 + 49 = 59.5 and perimeter you add all the sides so 3+7.6+7+7+7= 31.6
4 multiplied by 3.99 will = your answer....Please mark brainliest...
4(5x + 7) = 128
First, I'd do distributive property and get:
20x + 28 = 128
Then, subtract 28 from each side.
20x = 100
Next, I'd divide 100 by 20 = 5
x = 5
4 *(5(5) + 7) = 128
5 * 5 = 25
4 * (25 + 7)
4 * 32 = 128
Therefore, the perimeter = 2l + 2w
l = 4
w = 5x + 7
BUT we know that x = 5
w = 5(5) + 7 = 32
2(4) + 2(32)
8 + 64 = 72
Therefore, the perimeter would be 72 inches.