The answer is definatly C but if you know the answer why did you ask???
Anyway, hope this helps, and please mark brainliest!!!!!!!!!!!
Maria = x
Tom = y
Use substitution
x+y=30
2y=x
2y+y=30
3y=30
y=10
Tom is 10 years old.
x+y=30
x+10=30
x=20
Maria is 20 years old.
Answer:
its B :)
Step-by-step explanation:
I hope this helps ^^
A) The dimensions are (x+10) by (x+10).
B) The perimeter is given by 4x+40.
C) The perimeter when x is 4 is 56.
The quadratic can be factored by finding factors of c, the constant, that sum to b, the coefficient of x. Our c is 100 and our b is 20; we want factors of 100 that sum to 20. 10*10=100 and 10+10=20, so those are what we need. This gives us (x+10)(x+10 for the factored form.
Since the dimensions are all (x+10), and there are 4 sides, the perimeter is given by 4(x+10). Using the distributive property we have 4*x+4*10=4x+40.
To find the perimeter when x=4, substitute 4 into our perimeter expression:
4*4+40=16+40=56.
