Linear Equations: แบบฝึกหัด

Solve the linear equation \( 8x + 5 = 21 \).

A rectangular field has a length of \( (2x + 5) \) m and a width of \( (x - 2) \) m. If the perimeter is 42 m, find the value of \( x \).

Solve the linear equation \( 4(x - 3) = 20 \).

The sum of three consecutive integers is 72. Let the smallest integer be \( n \). Which equation can be used to find the value of \( n \)?

Solve the linear equation:
\( 9 - 4x = 25 \)

Solve the linear equation \( \frac{2x - 3}{5} = 3 \) for \( x \).

Solve the linear equation \( 3(2x - 5) = 4x + 7 \) for \( x \).

Consider the linear equation:
\( 7(x - 2) = 3x + 10 \)

(a) Solve the equation for \( x \).
(b) Using the value of \( x \) found in part (a), find the value of \( y \) if \( y = 2x^2 - 15 \).

The sum of three consecutive integers is 72.
(a) If the smallest integer is \( x \), write an equation to represent this information.
(b) Solve the equation to find the three integers.