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4 years ago

1. Solve for x: 3(2x – 1) – 10 = 8 + 5x A. -7 B. -3 C. 19 D. 21

Mathematics

2 answers:

pishuonlain [190]4 years ago

7 0

Answer:

D. 21

Step-by-step explanation:

Given equation: $\[3(2x – 1) – 10 = 8 + 5x\]
$

Simplifying:

$\[6x – 3 – 10 = 8 + 5x\]
$

=> $\[6x – 13 = 8 + 5x\]
$

=> $\[6x – 5x = 8 + 13\]
$

=> $\[(6 – 5)x = 21\]
$

=> $\[x = 21\]
$

Verifying by substituting the value of x in the equation:

Left Hand Side: $3(2x – 1) – 10$

$3(2*21 – 1) – 10$

= $3(42 – 1) – 10$

= $3(41) – 10$

= $123 – 10$

= $113$

Right Hand Side: $8 + 5x$

= $8 + 5*21$

= $8 + 105$

= $113$

So, Left Hand Side = Right Hand Side when x=21.

user100 [1]4 years ago

3 0

Answer:

(D) 21

Explanation:

3(2x−1)−10=8+5x

Step 1: Simplify both sides of the equation.

3(2x−1)−10=8+5x

(3)(2x)+(3)(−1)+−10=8+5x(Distribute)

6x+−3+−10=8+5x

(6x)+(−3+−10)=5x+8(Combine Like Terms)

6x+−13=5x+8

6x−13=5x+8

Step 2: Subtract 5x from both sides.

6x−13−5x=5x+8−5x

x−13=8

Step 3: Add 13 to both sides.

x−13+13=8+13

x=21

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