5 books for 12 dollars because you basically getting a book free
Answer:
Step-by-step explanation:
21 feet below is written as -21
9 feet up is written as +9
So we have -21 + 9 = -12 or 12 feet below sea level
The solution to system is x = 0 and y = -1
<em><u>Solution:</u></em>
<em><u>Given system of equations are:</u></em>
-8x + 2y = -2 ----------- eqn 1
4x + 4y = -4 ---------- eqn 2
We have to solve the system of equations
We can solve the equations by elimination method
<em><u>Multiply eqn 2 by 2</u></em>
8x + 8y = -8 ------ eqn 3
<em><u>Add eqn 1 and eqn 3</u></em>
-8x + 2y = -2
8x + 8y = -8
( + ) ---------------
0x + 2y + 8y = -2 - 8
10y = -10
Divide both sides by 10
y = -1
<em><u>Substitute y = -1 in eqn 1</u></em>
-8x + 2(-1) = -2
-8x - 2 = -2
-8x = -2 + 2
x = 0
Thus the solution to system is x = 0 and y = -1
3/2 since perpendicular lines have opposite reciprocal slopes
Given:
Two planks are each 1.5 m long.
One plank is 2.5m long.
To find:
The total length of all the three planks.
Solution:
Two planks are each 1.5 m long. So,
First plank = 1.5 m
Second plank = 1.5 m
One plank is 2.5m long. So,
Third plank = 2.5 m
Now, the total length of all the three planks is



Therefore, the total length of all the three planks is 5.5 m.