Answer:
Perimeter of Triangle: 

Step-by-step explanation:
The perimeter is the sum of all of the sides of the triangle.
Hence, the perimeter 
Since the perimeter is 90,
.
Subtract 15 from both sides:


Divide both sides by 6:


Answer:
one solution it is x=1
Step-by-step explanation:
i can type in the steps if you want
Answer:
7. is 5 - 35n
8. is -6x - 24
9. is 15m - 30
10. is 24p - 28
11. is 5b - 5
12. 5x + 45
RULE:
WHEN MULTIPLYING TWO NEGATIVES YOU WILL GET POSITIVE.
IF ONE IS NEGATIVE AND THE OTHER IS POSITIVE WHEN MULTIPLYING IT WILL BE NEGATIVE.
WHEN MULTIPLYING TWO POSITIVE NUMBERS IT WILL ALWAYS BE POSITIVE
SAME THING IF YOU MULTIPLY A POSITIVE NUMBER WITH A NEGATIVE NUMBER YOU GET A NEGATIVE AS YOUR ANSWER
YOU NEED ONE SIGN OF THE SAME WHEN MULTIPLYING TO BE A POSITIVE AS YOUR ANSWER
YOU NEED ONE SIGN TO BE DIFFERENT FROM THE OTHER WHEN MULTIPLYING TO GET A NEGATIVE AS YOUR ANSWER
2n=n-5 subtract n from both sides
n=-5
check...
2(-5)=(-5)-5
-10=-10
Answer:
C) 21 girls : 9 boys
Step-by-step explanation:
You just have to compare the ratio you're given to the answers and see if the ratios from the answers match up to the ratio you were given. The reason C is the answer is because if you divide by 3 in the ration, it is the same as the ratio you were given, 7:3