3 years ago

Is 10 the solution of the equation 4x - 8 = 31?

Mathematics

2 answers:

Tom [10]3 years ago

6 0

4x-8 = 31

4x = 31 + 8

4x = 39

x = 9.75

Vitek1552 [10]3 years ago

3 0

4x - 8 = 31
4x = 39
x = 9.75

You might be interested in

What is each of the expression written using each base only once? 10^10 x 10^10

aleksklad [387]

The answer is 10 thousand

4 0

2 years ago

4 - 5/2 * (1/10x) = 1 what is the value of x

Inga [223]

$4 - 5 / 2 * (1/10x) = 1\\$

The first step is to identify the order in which the equation must be solved, by following PEMDAS (you might know it as BEDMAS):

Parenthesis (or Brackets)

Exponents

Multiplication and Division

Addition and Subtraction

My advice would be to add parenthesis, following these rules, if you are not very good at finding them immediately by sight.

So:

$4 - 5 / 2 * (\frac{1}{10x}) = 1\\\\4 - [(5/2)*(\frac{1}{10x})]=1\\\\4-(2.5*\frac{1}{10x})=1\\\\4-\frac{2.5}{10x}-1=0\\3-\frac{x}{4}=0\\\frac{x}{4}=3\\x=3*4\\x=12$

We check our answer:

$x=12\\4 - [(5 / 2) * (1/10)*(x)] = 1\\4 - [(5 / 2) * (\frac{1}{10}) * (12))] = 1\\4 - [2.5 * (\frac{1}{10})*12] = 1\\4 - [(\frac{2.5}{10})*12] = 1\\4 - [(\frac{1}{4})*12] = 1\\4 - 3 = 1\\1=1$