what is 2x + 5 = 9x – 16?

21 = 7x
x = 3

2x + 5 = 9x - 16
7x = 21
x = 3

Answer: x = 3

Proof:
2(3) + 5 = 9(3) - 16
6 + 5 = 27 - 16
11 = 11

2x + 5 = 9x - 16
2x - 9x = -5 - 16
-7x = -21
x = -21/-7
x = 21/7
x = 3

x=3

X = 3

2x+5=9x-16
2x-9x= -16-5
-7x= -21
x=3

9x - 2x = 5 + 16
7x = 21
x = 3

2x-9x=-16-5
-7x=-21
x=3

When you are attempting to solve a first-degree equation with one unknown variable you should follow this strategy:

1. Move the (x-terms) to one side and the (constant terms) to the other side.

Moving terms from one side to another in an equation means that you add the negation of that value to both sides of the equation.

So in our case, 2x + 5 = 9x - 16
We wish to move 9x from the right side to the left side.
So we add -(9x) to the both sides to make sure that the equation still holds true (since adding same value to both sides will keep it balanced)

2x + 5 - 9x = 9x - 16 - 9x, simplify to get:
2x + 5 - 9x = -16 notice here how 9x - 9x cancel on the right

a quick way to think of this is to imagine that you move it from one side to another but you change the "sign".

Now lets move 5 to the right side:
2x - 9x = -16 - 5


2. When you are done moving all terms, combine them:
2x - 9x = -16 - 5
-7x = -21

3. Now to get the value of x, you'll need to get rid of the coefficient which is in this case (-7)

To do this, you'll need to multiply the equation by its reciprocal
which is (1/(-7)).

(-1/7) * (-7x) = (-1/7) * (-21)
When you multiply a value by its reciprocal you'll get 1, so:

x = 21/7
x = 3 , this is the solution of your equation.

another example is:

(1/4)x + 3 = -5 + (3/4)x
Moving (3/4)x to left and 3 to right:
(1/4)x - (3/4)x = -5 - 3
Combining terms:
(-2/4)x = -8
Multiplying by (-4/2):
(-4/2) * (-2/4)x = (-4/2) * (-8)
x = 32/2
x = 16

First thing to do is make sure we have all the variables on one side of the equation, and all of the constants on the other side (constant = any number that doesn't have a variable attached to it).

2x + 5 = 9x – 16

Subtract 2x from both sides.

2x + 5 -2x = 9x – 16 - 2x

Which becomes

5 = 7x - 16.

Add 16 to both sides.

5 + 16 = 7x -16 + 16

21 = 7x

Divide both sides by 7.

21/7 = 7x/7

3 = x