105 and 75 because 75 +30 = 105 and 75+105=180
The diagonal of a rectangle = sqrt(w^2 + l^2)
w = width
l = length
In this problem,
The diagonal = 20 in
w = x
l = 2x + 8
Let's plug our numbers into the formula above.
20in = sqrt((x)^2 + (2x + 8)^2)
Let's simplify the inside of the sqrt
20 in = sqrt(5x^2 + 32x + 64)
Now, let's square both sides.
400 = 5x^2 + 32x + 64
Subtract 400 from both sides.
0 = 5x^2 + 32x - 336
Factor
0 = (5x - 28)(x + 12)
Set both terms equal to zero and solve.
x + 12 = 0
Subtract 12 from both sides.
x = -12
5x - 28 = 0
Add 28 to both sides.
5x = 28
Divide both sides by 5
x = 28/5
The width cant be a negative number so now we know that the only real solution is 28/5
Let's plug 28/5 into our length equation.
Length = 2(28/5) + 8 = 56/5 + 8 = 96/5
In conclusion,
Length = 96/5 inches
Width = 28/5
Answer:
C
Step-by-step explanation:
In this question, we're trying to find cost of one sandwich.
To find this, we must make a systems of equation from the given information:
We would represent sandwiches as "s" and drinks as "d".
Systems of equations:
6s + 4d = 53
4s + 6d = 47
Solve for s:
6(6s + 4d = 53)
-4(4s + 6d = 47)
36s + 24d = 318
-16s - 24d = -188
--------------------------
20s = 130
Divide both sides by s
s = 6.50
This means that one sandwich costs $6.50
Answer:
$6.50