Answer:
set mary is x years old, and helen is y years old.
first sentence:x=2y
second one:4(y-8)=x+4
bring x=2y in 4(y-8)=x+4
=>4y-32=2y+4
=>2y=36
=>y=18
=>x=36
mary:36
helen:18
Answer:
Algebraically, f is even if and only if f(-x) = f(x) for all x in the domain of f. A function f is odd if the graph of f is symmetric with respect to the origin. Algebraically, f is odd if and only if f(-x) = -f(x) for all x in the domain of f.
Step-by-step explanation:
So we will be using
form, in which m = slope and b = y-intercept. Since we know the slope (-8), all we need to do is solve for the y-intercept. We can do this by inserting (-2,2) into the equation and solve for b.

Firstly, do the multiplication: 
Next, subtract 16 on both sides, and your answer will be -14 = b
Using the previous info we have, our equation is y = -8x - 14
Answer:
Angle kjm is 56 °
you equate 7x with 3x +16
ie
3x + 16 = 7x