Which equations have the same value of [tex]$x$[/tex] as [tex]\frac{3}{5}(30x-15)=72[/tex]? Select three options.

A. [tex]18x-15=72[/tex]

B. [tex]50x-25=72[/tex]

C. [tex]18x-9=72[/tex]

D. [tex]3(6x-3)=72[/tex]

E. [tex]x=4.5[/tex]



Answer :

Sure! Let's find out which of these equations have the same value for [tex]\( x \)[/tex] as the given equation [tex]\(\frac{3}{5}(30x - 15) = 72\)[/tex].

1. Solving the Original Equation:
[tex]\[ \frac{3}{5}(30x - 15) = 72 \][/tex]

Step 1: Eliminate the fraction by multiplying both sides by 5:
[tex]\[ 3(30x - 15) = 360 \][/tex]

Step 2: Simplify inside the parentheses:
[tex]\[ 90x - 45 = 360 \][/tex]

Step 3: Add 45 to both sides to isolate the term with [tex]\( x \)[/tex]:
[tex]\[ 90x = 405 \][/tex]

Step 4: Divide both sides by 90 to solve for [tex]\( x \)[/tex]:
[tex]\[ x = \frac{405}{90} = 4.5 \][/tex]

So, the value of [tex]\( x \)[/tex] is [tex]\( 4.5 \)[/tex].

2. Checking Given Equations for the Same Value of [tex]\( x \)[/tex]:

(1) Equation: [tex]\( 18x - 15 = 72 \)[/tex]

Substitute [tex]\( x = 4.5 \)[/tex]:
[tex]\[ 18(4.5) - 15 = 81 - 15 = 66 \quad \text{(does not equal 72)} \][/tex]

This equation does not have the same value of [tex]\( x \)[/tex].

(2) Equation: [tex]\( 50x - 25 = 72 \)[/tex]

Substitute [tex]\( x = 4.5 \)[/tex]:
[tex]\[ 50(4.5) - 25 = 225 - 25 = 200 \quad \text{(does not equal 72)} \][/tex]

This equation does not have the same value of [tex]\( x \)[/tex].

(3) Equation: [tex]\( 18x - 9 = 72 \)[/tex]

Substitute [tex]\( x = 4.5 \)[/tex]:
[tex]\[ 18(4.5) - 9 = 81 - 9 = 72 \][/tex]

This equation has the same value of [tex]\( x \)[/tex].

(4) Equation: [tex]\( 3(6x - 3) = 72 \)[/tex]

Substitute [tex]\( x = 4.5 \)[/tex]:
[tex]\[ 3(6(4.5) - 3) = 3(27 - 3) = 3(24) = 72 \][/tex]

This equation has the same value of [tex]\( x \)[/tex].

(5) Equation: [tex]\( x = 4.5 \)[/tex]

This directly matches the value [tex]\( x = 4.5 \)[/tex].

Therefore, the three equations that have the same value for [tex]\( x \)[/tex] as [tex]\(\frac{3}{5}(30x - 15) = 72\)[/tex] are:
1. [tex]\( 18x - 9 = 72 \)[/tex]
2. [tex]\( 3(6x - 3) = 72 \)[/tex]
3. [tex]\( x = 4.5 \)[/tex]

Hence, the correct options are:
- [tex]\( 18x - 9 = 72 \)[/tex]
- [tex]\( 3(6x - 3) = 72 \)[/tex]
- [tex]\( x = 4.5 \)[/tex]