The two problems are almost identical: you have to set up a system, and then solve it.
In the first case, let 
and 
be, respectively, the number of girls and boys.
We know that 
(the number of girls in the Spanish Club is four more than twice the number of boys). Also, we know that 
(there are 61 students in total).
So, we have the system
We can use the first equation to substitute in the second
And then solve for :
For the second problem, let 
and 
be the number of pins knocked down by, respectively, Carrie and John. Just like before, we have the system
And you can solve it in the very same way we solved the previous one.
Answer:
X = 5
Step-by-step explanation:
Here is what I am picturing (not to scale)
A ----------------B-----------C
We are given the information of AB (which equals 3x + 1), BC (which equals 4x - 5), and AC (which equals 8x - 9).
With reference to the line, AB + BC = AC
So,
3x + 1 + 4x - 5 = 8x - 9
7x - 4 = 8x - 9
5 = x
x + 24 = first angle
x = second angle
4x = third angle
x + 24 + x + 4x = 180°
6x + 24 = 180°
6x = 180° - 24
6x = 156°
x = 156° ÷ 6
x = 26°....the second angle.
x + 24 = 26 + 24 = 50°.... the first angle.
4(26) = 104°
The largest angle is the third angle, which measures 104°.
I believe it is C is the answer
