Answer:
25
Step-by-step explanation:
5=20% of x
0.20x=5
divide both sides by 0.20
x=25
Answer:
Step-by-step explanation:
xy = 300
x + y = 50 Solve for y
y = 50 - x substitute into xy = 300
x(50 - x) = 300 Remove the brackets.
50x - x^2 = 300 Bring the left to the right.
0 = x^2 - 50x + 300
This is a quadratic. It will have 2 solutions.
a=1
b = - 50
c = 300
Put these into the quadratic equation.
It turns out that x has two values -- both plus
x1 = 42.03
x2 = 6.97
x1 + y1 = 50
42.03 + y = 50
y = 50 - 42.03
y = 7,97
(42.03 , 7.97)
====================
x2 + y2 = 50
6.97 + y2 = 50
y2 = 50 - 6.97
y2 = 43.03
(6.97 , 43.03)
Answer:
7
Step-by-step explanation:
7
1st is D
2nd is
5x + 4 + 7x + 2 = 90
12x + 6 = 90
12x = 84
x = 7
