All categories

3 years ago

7(2x-5)=21 What is x?

Mathematics

1 answer:

Over [174]3 years ago

6 0

Answer:

x = 4

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Step-by-step explanation:

Step 1: Define Equation

7(2x - 5) = 21

Step 2: Solve for x

Distribute 7: 2x - 5 = 3
Isolate x term: 2x = 8
Isolate x: x = 4

Step 3: Check

Plug in x into the original equation to verify it's a solution.

Substitute in x: 7(2(4) - 5) = 21
Multiply: 7(8 - 5) = 21
Subtract: 7(3) = 21
Multiply: 21 = 21

Here we see that 21 does indeed equal 21.

∴ x = 4 is the solution to the equation.

You might be interested in

Part A: Solve −np − 70 < 40 for n. Show your work. (4 points) Part B: Solve 4w − 7k = 28 for k. Show your work. (6 points

likoan [24]

For part A, lets write the problem

$-np - 70\ \textless \ 40$

add $70$ to both sides

$-np - 70 + 70 \ \textless \ 40 + 70

-np \ \textless \ 110$

we are going to reverse the inequality, to do this we are going to multiply both sides by $-1$

$(-np ) ( -1 ) \ \textgreater \ 110 ( -1 )$

$pn \ \textgreater \ -110$

divide both sides by $p$

$\frac{pn}{p} \ \textgreater \ \frac{-110}{p}$

our answer would be

$n \ \textgreater \ \frac{-110}{p}$

lets go with part b, lets write the problem

$4w - 7k = 28$

subtract $4w$ from both sides

$4w - 7k - 4w = 28 - 4w$

$-7k = 28 - 4w$

divide both sides by $-7$

$\frac{-7k}{-7} = \frac{28}{-7} - \frac{4w}{-7}$

I few simplified it, we would be left with,

$k = -\frac{28 - 4w }{7}$

I hope this helped!!

- Kiana

7 0

4 years ago

Identify the polynomial.

Alexxandr [17]

Answer:

it's a trinomial

7 0

3 years ago

Select the correct aswer.

Alex73 [517]

I think it is c but if smn has a different answer do with that instead

4 0

3 years ago

A stick 42 inches long is broken into two pieces, so that one piece is twice as long as the other one. How long are the two piec

krek1111 [17]

Total length of stick = 42 inches.

Let the shorter piece be x inches.

Thus, the longer piece is 2x.

2x + x = 42

3x = 42

x = 14

Therefore, the length of the two pieces are 14 inches and 28 inches.

7 0

4 years ago

Classify each of the following using the most specific set of Rational Numbers:

Sati [7]

Yeah cuhh i’m jus like big steppa

8 0

4 years ago

Read 2 more answers