Using a system of equations, it is found that he bought 18 twigs.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variable is the amount n.
Nine times the square of the twigs he bought there Is half of their cube, hence the equation is:
Then, applying cross multiplication:
He bought 18 twigs.
To learn more about a system of equations, you can check brainly.com/question/24342899
Answer: 10
Step-by-step explanation:
We know the perimeter is the total sum of all sides of the shape, we can use this to form an equation: the perimeter=1st side + 2nd side + 3rd side + 4th side 39a-7=9a+(5a+1)+(17a-6)+4th side.
Collect like terms to get 39a-7=31a-5+4th side
If we move everything but the 4th side over to the left we can solve
C. 8a-2=4th side is the correct answer
Yes, 60 can go into 90.
You can determine this by dividing 90 by 60.
90 / 60 = 1.5
Sixty can go into ninety 1.5 times.
I hope his helps!