This is the second part (questions 11-20) of the solutions of the Grade 8 MTAP 2015 Elimination Questions. You can read the solutions for questions 1-10 here. If you found any errors in the solution, please comment in the box below.
11.) If and
, what is
?
Solution
Answer: -12
12.) Simplify .
Solution
Answer:
13.) If and
are positive constants, simplify
.
Solution
Note that ,
and
Now
This is already correct, but if you want your answer in radical form, the previous expression can be converted to
Answer: or
14.) What is the quotient when is divided by
?
Solution
Answer: remainder
.
15.) In Item 14, what is the remainder?
Answer:
16.) If , what is
?
Solution
Answer:
17.) If and
, what is
?
Solution
and
Substituting the given values above,
.
Answer: 238
18.) If the length, width, and height of an open-top rectangular box are cm,
cm, and
cm, what is its surface area?
Solution
The formula for finding the surface area of a rectangular prism with length
, width
and height
is
. Since the box is open, we subtract lw, which is the top face. So, the surface area of the open box is
.
Substituting, we have
Answer:
19.) A man walked km for 2.5 hrs, then jogged
km for 3.5 hrs, and finally walked again
km for 4 hrs. If his average speed for the entire exercise was 4 kph, what is x?
Solution
Answer: 3/5 or 0.6
20.) Simplify .
Solution
We can group the expressions as sum and difference of two cubes.
Now, this is in the form of the difference of two squares .
So,
Answer: