Respuesta :

Answer:

(a) [tex]10x + 35y = 55[/tex]

(b) [tex]y = \frac{11 - 2x}{7}[/tex]

Step-by-step explanation:

Given

[tex]2x + 7y = 11[/tex]

Solving (a): Multiply equation by 5.

Multiply both sides by 5

[tex]5 * (2x + 7y) = 11*5[/tex]

Open bracket

[tex]5 * 2x + 5 * 7y = 11*5[/tex]

[tex]10x + 35y = 55[/tex]

(b) Solve for y in [tex]10x + 35y = 55[/tex] and [tex]2x + 7y = 11[/tex]

[tex]10x + 35y = 55[/tex]

Subtract 10x from both sides

[tex]35y = 55 - 10x[/tex]

Divide both sides by 35

[tex]\frac{35y}{35} = \frac{55 - 10x}{35}[/tex]

[tex]y = \frac{55 - 10x}{35}[/tex]

Factorize the numerator:

[tex]y = \frac{5(11 - 2x)}{35}[/tex]

Express 35 as 7 * 5

[tex]y = \frac{5(11 - 2x)}{7 * 5}[/tex]

[tex]y = \frac{(11 - 2x)}{7}[/tex]

[tex]y = \frac{11 - 2x}{7}[/tex]

When [tex]2x + 7y = 11[/tex] is solved, the solution will be: [tex]y = \frac{11 - 2x}{7}[/tex]