Answer:
Step-by-step explanation:
4b - 6d = 4*7 - 6*3
= 28 - 18
= 10
Answer:
x + y = 745
23.50x + 58.75y = 29,668.75
Step-by-step explanation:
Since 745 copies were sold and x represents the number of copies of the home edition sold and y represents the number of copies of the business edition sold:
x + y = 745
Since the home edition costs $23.50, and the business edition costs $58.75:
The money earned from home edition is = 23.50x
The money earned from business edition is = 58.75y
Since the company earned $29,668.75:
23.50x + 58.75y = 29,668.75
First square both sides to get:
c + 22 = (c + 2)^2
or
c + 22 = c^2 + 4c + 4
Move the terms on the left side to the right side:
c^2 + 3c - 18 = 0
Factor to get:
(c + 6) * (c - 3) = 0.
The solutions are c = -6 and c = 3.
Check to see if these answers work by plugging them into the original equation:
c = -6:
sqrt (-6 + 22) ?= -6 + 2
But, -6 + 2 is a negative number, and you can't get a negative from a square root. So, -6 is extraneous.
c = 3:
sqrt (3 + 22) ?= 3 + 2
5 = 5. So, 3 works.
The answer is: B
