Question

solve the following simultaneous equation ( by the method of elimination)


plz tell me how will i do this sum

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Answer 1

Answer:

x = 36 , y = 12

Step-by-step explanation:

Given :

To find the value of x & y,

if,

$x + y = 48$  ...(i)

&

$x + 4 = \frac{5}{2} (y + 4)$ ...(ii)

Solution :

From (ii)

⇒ $x + 4 = \frac{5}{2} (y + 4)$

⇒ $x + 4 = \frac{5}{2} (y) + \frac{5}{2} (4)$

⇒ $x + 4 = \frac{5}{2} (y) + 10$

⇒ $x = \frac{5}{2} (y)+10 - 4$

⇒ $x-\frac{5}{2} (y) = 6$

⇒ $2x-5y = 12$ ..(iii)

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By adding 5 × (i) + (ii)

⇒ 5 (x + y) + (2x - y) = 5 (48) + 12

⇒ 5x + 5y + 2x - 5y = 240+12

⇒ 7x = 252

⇒ x = $\frac{252}{7}$

⇒ x = 36

By substituting the value of x in (i),

⇒ x + y  48

⇒ 36 + y = 48

⇒ y = 48 - 36

⇒ y = 12,.