2x+10=0
subtract 10 from both sides
2x=(-10)
divide 2 from both sides
x=-5
For this case we have the following data:


So that the figure can be a rectangle, its diagonals must be equal, that is, 
In this way we have:

Clearing x we have:


Thus, x must be equal to 10 so that the figure is a rectangle.
Answer:

Option A
Answer:
Simplifying
3n + 7 + -2 = 0
Reorder the terms:
7 + -2 + 3n = 0
Combine like terms: 7 + -2 = 5
5 + 3n = 0
Solving
5 + 3n = 0
Solving for variable 'n'.
Move all terms containing n to the left, all other terms to the right.
Add '-5' to each side of the equation.
5 + -5 + 3n = 0 + -5
Combine like terms: 5 + -5 = 0
0 + 3n = 0 + -5
3n = 0 + -5
Combine like terms: 0 + -5 = -5
3n = -5
Divide each side by '3'.
n = -1.666666667
Simplifying
n = -1.666666667
Step-by-step explanation:
I think the correct answer might be A or D
Answer:
$ 150
Step-by-step explanation:
Given:
Cost price of a microwave = $105
Discount % = 30
Question asked:
what was the price of the microwave before sale = ?
Solution:
Let the price of the microwave before sale = 
Price before sale - 30 % discount = cost price of microwave (by Javier)



Multiplying both side by 100


Dividing both side by 70

x = price of the microwave before sale = $ 150
Thus, price of the microwave before the sale = $150