The answer is B! I think!
<h2>
Hello!</h2>
The answer is:
It takes Ella 3 seconds to do a push-up and 3 seconds to do a sit up.
<h2>Why?</h2>
To find how many seconds Ella took to do a push-up and a sit-up we must write two equations using the given information.
Let be "x" the time needed to push-ups and "y" be the time needed to do sit-ups.
So, writing the equations we have:
First equation,
If she can do 13 push-ups and 7 sit-ups in 60 seconds, we have:

Second equation,
If she can do 13 push-ups and 19 sit-ups in 96 seconds, we have:

Now, creating a system of equations, and using the reduction method to solve it, we have:

Multiplying the first equation by -1, we have:


Then, substituting "y" into the first equation, we have:





Hence, we have that It takes Ella 3 seconds to do a push-up and 3 seconds to do a sit up.
Have a nice day!
Answer:
=
2
5
Step-by-step explanation:
−
2
0
=
5
n-20=5
n−20=5
−
2
0
+
2
0
=
5
+
2
0
Answer:
p=3 q=0
Step-by-step explanation:
p+2q=3
p-2q=3
p+2q=3
p=3-2q---------eqn i
p-2q=3
3-2q-2q=3
3-4q=3
-4q=3-3
q=0÷-4
q=0
putting the value of q in equation i
p=3-2q
=3-2×0
=3