Assume x are Erica's classes & y are Bo's classes.
x+y=35
x=2y-13
Replacing the value of x into the first equation
2y-13+y=35
3y=35+13
y=16 classes
x=2*16-13=19 classes
9514 1404 393
Answer:
B, D
Step-by-step explanation:
The quadratic expands to ...
(2n -1)² = (2n)² +2(2n)(-1) +(-1)² = 4n² -4n +1
The coefficients can be factored out of the sum, so ...
∑(4n²) = 4∑n² for example
The sum of 60 ones is 60:

So, the sum can be written as ...

_____
It appears that the key to choosing the correct answers is paying attention to signs.
Answer:
the answer is 9 and 8
Step-by-step explanation:
because 9 times 8 equal 72 which means 9 and 8 can be found as a square root of 72.
hope this help can you give me brainliest
In an acute triangle all angles must be acute ( or less than 90°)
Answer: C ) 50°, 55°, 75°
A) and D ) are an obtuse and B ) is a right triangle.