Question

А) 4(x + 1) + 11 = 31; б) 7 – 2x – 3(5x – 2) = 47; в) (2x – 0,1) + (3x – 5) = 7; г ) (x – 0,2) + (4x – 3) = 8.

Answer 1

Ответ:

$1) \ 4(x + 1) + 11 = 31 \\ 4x + 4 + 11 = 31 \\ 4x = 31 - 4 - 11 \\ 4x = 16 \\ x = 16 \div 4 \\ x = 4.$

$2) \ 7 - 2x - 3(5x - 2) = 47 \\ 7 - 2x - 15x + 6 = 47 \\ - 17x = 47 - 7 - 6 \\ - 17x = 34 \\ x = 34 \div ( - 17) \\ x = - 2.$

$3) \ (2x - 0,1) + (3x - 5) = 7\\ 2x - 0,1 + 3x - 5 = 7 \\ 5x = 7 + 0,1 + 5 \\ 5x = 12,1 \\ x = 12,1 \div 5 \\ x = 2,42.$

$4) \ (x - 0,2) + (4x - 3) = 8. \\ x - 0,2 + 4x - 3 = 8 \\ 5x = 8 + 0,2 + 3 \\ 5x = 11,2 \\ x = 11,2 \div 5 \\ x = 2,24.$

Answer 2

Sure, I can help you solve these equations step by step.

а) $4(x + 1) + 11 = 31$

First, distribute 4 into $x + 1$:

$4x + 4 + 11 = 31$

Combine like terms:

$4x + 15 = 31$

Now, isolate $x$ by subtracting 15 from both sides:

$4x = 31 - 15$

$4x = 16$

Finally, divide both sides by 4 to solve for $x$:

$x = \frac{16}{4}$

$x = 4$

б) $7 - 2x - 3(5x - 2) = 47$

First, distribute $-3$ into $5x - 2$:

$7 - 2x - 15x + 6 = 47$

Combine like terms:

$-17x + 13 = 47$

Now, isolate $x$ by subtracting 13 from both sides:

$-17x = 47 - 13$

$-17x = 34$

Finally, divide both sides by $-17$ to solve for $x$:

$x = \frac{34}{-17}$

$x = -2$

в) $(2x - 0.1) + (3x - 5) = 7$

First, combine like terms:

$2x - 0.1 + 3x - 5 = 7$

Combine $x$ terms and constants:

$5x - 5.1 = 7$

Now, isolate $x$ by adding 5.1 to both sides:

$5x = 7 + 5.1$

$5x = 12.1$

Finally, divide both sides by 5 to solve for $x$:

$x = \frac{12.1}{5}$

$x \approx 2.42$

г) $(x - 0.2) + (4x - 3) = 8$

First, combine like terms:

$x - 0.2 + 4x - 3 = 8$

Combine $x$ terms and constants:

$5x - 3.2 = 8$

Now, isolate $x$ by adding 3.2 to both sides:

$5x = 8 + 3.2$

$5x = 11.2$

Finally, divide both sides by 5 to solve for $x$:

$x = \frac{11.2}{5}$

$x \approx 2.24$