Answer:
9 years old.
Step-by-step explanation:
Since the ages of all of these students are being represented in relation to the middle student's age then we can create formulas for each student and then apply them to the formula for the sum of their ages and solve for the middle child's age (M) like so... (oldest child's age is represented by variable O and youngest child's age is represented by variable Y)
O = M + 6
Y = M - 3
30 = (M+6) + M + (M-3) ... combine like terms
30 = 3M + 3 ... subtract 3 from both sides
27 = 3M ... divide both sides by 3
9 = M
Now we know that the middle child is 9 years old.
Answer:
110
Step-by-step explanation:
use a calculator bbbbbbbbbbbb
114
Just use the Pythagorean theorem and then multiply by 2 to find answer. See picture to see how I did it.
Since bot of the expressions in x are equal to y we can equate them as follows:-
6x + 9 = 7x + 7
9 - 7 = 7x - 6x
x = 2
and y = 6(2) + 9 = 21
THe answer is Choice B
Answer:
X=4
Step-by-step explanation:
7x+4y=28
7x+4(0)=28
7x=28
X=4
