Answer:
7
Step-by-step explanation:
9×7 = 63
Answer:
The answer is 40
Step-by-step explanation:
55-15=40
Answer:C 5a^2 +70a +240
Step-by-step explanation:
<span>Let the number of nickles be x
Let the number of pennies be y
Value Value
Type Number of of
of of EACH ALL
coin coins coin coins
-------------------------------------------
nickles x $0.05 $0.05x
pennies y $0.01 $0.01y
-------------------------------------------
TOTALS 56 ----- $1.52
The first equation comes from the second column.</span>
Given

We have to set the restraint

because a square root is non-negative, and thus it can't equal a negative number. With this in mind, we can square both sides:

The solutions to this equation are 7 and -2. Recalling that we can only accept solutions greater than or equal to -1, 7 is a feasible solution, while -2 is extraneous.
Similarly, we have

So, we have to impose

Squaring both sides, we have

The solutions to this equation are 5 and 10. Since we only accept solutions greater than or equal to 7, 10 is a feasible solution, while 5 is extraneous.