Answer:
Helena gave the answer as (7y²z + 6yz²- 5 - 3yz² + 2) which is equivalent to (7y²z + 3yz² - 3).
Step-by-step explanation:
Misha's group was asked to write an expression equivalent to
7y²z + 3yz² - 3
When Mr. Chen checked their answers, he found only one to be correct.
And she was Helena.
Helena gave the answer as (7y²z + 6yz²- 5 - 3yz² + 2) which is equivalent to (7y²z + 3yz² - 3).
Because, (7y²z + 6yz²- 5 - 3yz² + 2)
= 7y²z + (6yz² - 3yz²) - (5 - 2)
= 7y²z + 3yz² - 3 (Answer)
Answer:

Step-by-step explanation:
Pythagorean theorem is:


Isolate x by adding 8 to both sides.
3 = x/3
Then, multiply by 3 on both sides.
9 = x
To prove that this is right, you can imput 9 into the equation and it equals -5.
Answer:
x = k - 3
Step-by-step explanation:
Given parameters:
Gradient of the line = 5;
Coordinates; M(x, 8)
N(k, 23)
Solution:
If we use the expression for finding the slope of the line, we can solve this problem;
Slope = 
where
x₁ = x y₁ = 8
x₂ = k y₂ = 23
Input the parameters:
5 = 
15 = 5(k - x)
3= k- x
k - x = 3
Express x in terms of k;
-x = 3 - k
Multiply through by -1;
x = -3 + k
x = k - 3
70 is a composite number because it can be divided by numbers other than one and itself.