Answer:
rational
Step-by-step explanation:
Given the system of equations:

To solve it by substitution, follow the steps below.
Step 1: Solve one linear equation for x in terms of y.
Let's choose the second equation. To solve it for x, add 3y to each side of the equations.

Step 2: Substitute the expression found for x in the first equation.

Step 3: Isolate y in the equation found in step 2.
To do it, first, add 48 to both sides.

Then, divide both sides by 15.

Step 4: Substitute y by 5 in the relation found in step 1 to find x.

Answer:
x = -9
y = 5
or (-9, 5)
Also, you can graph the lines by choosing two points from each equation, according to the picture below.
Answer:

Step-by-step explanation:
<u>Sequential Operations
</u>
Mathematical operations can be done in sequence or in batches if they are of the same type. For example, we can add many terms in one single operation, but we cannot add and multiply in one go, because there are priorities when dealing with products and sums. Same happens with powers.
In our problem we are required to perform a sequence of operations like follows
Add s to t:

Add the result to r

Raise what you have to the 7th power

This is the final result
Answer: 66cm
Step-by-step explanation:
Diameter (d) = 21 cm
c= πd = 22/7 x 21 = 22 x 3 = 66cm