Answer:
x=# of boys
x+7=# of girls
x+x+7=25
2x+7=25
2x=25-7
2x=18
x=18/2
x=9 boys
x+7=16 girls
If you don't understand variables use trial and error.
Boys Girls
1 8
2 9
3 10
4 11
5 12
6 13
7 14
8 15
9 16 9+16=25 students
You could start this way...
Boys Girls
12 13
11 14
10 15
9 16 16 is 7 more than 9
Answer:
The solution to the inequality is 0.
Answer:
Nolan takes 100s
Step-by-step explanation:
x = x - 15x/100
x = 0.85x
x = 85/0.85
x = 100s
You FOIL
9x^2-15x+21x-35
Combine like terms
9x^2 + 6x - 35
<h3>Answer:</h3>
a) l = 5 + 2w
b) P = 2(l +w) = 2(5 +2w +w)
c) w = 8 cm, l = 21 cm
<h3>Explanation:</h3>
a) Using w for width, twice the width is 2w, and 5 more than that is 5+2w. This is your expression for l:
... l = 5 + 2w
b) The perimeter is the sum of the lengths of all sides, so is the sum of twice the length and twice the width.
... P = 2(l +w) = 2(5 +2w + w) . . . . substituting for l using the expression of (a)
c) Substituting the given perimeter, we have ...
... 58 = 2(5 +3w) = 10 + 6w . . . . . collect terms, eliminate parentheses
... 48 = 6w . . . . . . . . . . . . . . . . . . subtract 10
... 8 = w . . . . . . . . divide by 6
... l = 5 + 2·8 = 21 . . . . . find length using the formula for it
Dimensions are in centimeters, so we can write the solution as ...
- width = 8 cm
- length = 21 cm