Solve the system of equations by substitution.
Given equations:
To find :
Put value of y of second equation (i.e y = 4x) in equation one (i.e x + y = 15)
➞ x + y = 15
➞ x + 4x = 15
➞ 5x = 15
Divide both LHS and RHS by 5
➞ (5x)/5 = 15/5
➞ x/1 = 3/1
➞ x = 3
Now put value of x in equation 2
{Note : value of x can be inserted both in equation 1 and 2}
➞ y = 4x
➞ y = 4 × 3
➞y = 12
Verification :
put value of x and y in equation 1 :
LHS = RHS
hence verified !
put value of x and y in equation 2 :
LHS = RHS
hence verified !
∴ Value of x and y is 3 and 12 respectedly .
REQUIRED ANSWER :
(x , y) = (3 , 12)
Answer:
(3, 12)
Step-by-step explanation:
Given equations:
Substitute Equation 2 into Equation 1 and solve for x:
⇒ x + 4x = 15
⇒ 5x = 15
⇒ x = 15 ÷ 5
⇒ x = 3
Substitute the found value of x into Equation 2 and solve for y:
⇒ y = 4(3)
⇒ y = 12
Therefore, the solution of the system is (3, 12)