Answer: options b and c
<u>Step-by-step explanation:</u>
∠ACD is supplementary to ∠ACE <em>given</em>
∠ACD is supplementary to ∠BCD <em>given</em>
⇒ ∠ACE is supplementary to ∠BCD <em>transitive property</em>
∠ACD ≅ ∠BCE <em>given</em>
⇒ ∠BCE is supplementary to ∠ACE <em>substitution</em>
and ∠BCE is supplementary to ∠BCD <em>substitution</em>
********************************************************************************
multiple choice options:
a) ∠ACE is supplementary to ∠BCD <em>False</em>
b) ∠BCE is supplementary to ∠ACE <em>TRUE</em>
c) ∠BCD is supplementary to ∠BCE <em>TRUE</em>
d) ∠ACE ≅ ∠BCE <em> False</em>
e) ∠BCD ≅ ∠ACE <em>False</em>
Answer:
The chemist needs to add 400mL of 40% solution.
Step-by-step explanation:
The equation

gives the percent concentration
of the final mixture, when
mL of the 40% solution are added.
Now we are asked, how many milliliters
of the 40% solution should the chemist add to get final percent concentration
; this is just a matter of solving the equation

and we solve it the following way:

Thus, the chemist needs 400mL of 40% solution to get 30% concentration of the final mixture.
It's like an equal sign but with 3 lines, not two
like this <span>≡
</span>I think it's called a triple bar.
A. Thay intersect at one point.
Answer:
14. 4 + x - 2
15. 8k - 3k
16. 5 + 2y + 15
Step-by-step explanation:
14. "sum" means adding, "minus" means subtract
sum of four and x: 4 + x
minus two: 4 + x - 2
15. "product" means multiplying, "decreased by" means subtract, "times" means multiply
the product of k and 8: 8k
three times k: 3k
the product of k and 8 decreased by three times k: 8k - 3k
(Depending on what the question is asking, you may or may not need to simplify this to 5k (8k - 3k = 5k))
16. "more" means add, "plus" means add, "twice" means multiply by two
five: 5
plus twice y: 5 + 2y
fifteen more: 5 + 2y + 15