Question

0.4x +0.3y=1.7 and 0.7x-0.2y=0.8 by elimination method

Answer 1

as/q
0.4x + 0.3y=1.7...(1)
0.7x - 0.2y= 0.8...(2)
multiplying eq 1 by 2 & eq 2 by 3, we get
0.8x + 0.6y = 3.4..(3)
2.1x - 0.6y = 2.4..(4) now adding eq 3&4
2.9x= 5.8
x=5.8/2.9
x=2
putting the value of x in eq (1)
0.4×2 + 0.3y=1.7
0.3y= 1.7-0.8
y=0.9/0.3
y=3
Answer x=2 y=3

Answer 2

Answer:

When we solve the equation $0.4x+0.3y = 1.7$ and $0.7x-0.2y = 0.8$ by the elimination method we get x = 2 & y = 3.

Step-by-step explanation:

We have two equations as

$0.4x+0.3y = 1.7$ .....(1)and

$0.7x-0.2y = 0.8$   ....(2)

and it is asked to solve for x and y by elimination method which can be done as

Step 1 of 3

Multiply the eq(1) with 2 and eq(2) by 3 we get

0.8x + 0.6y = 3.4   ....(3)

2.1x -0.6y = 2.4      ....(4)

Step 2 of 3

Now by adding eq(3) and eq(4) we get

2.9x = 5.8

⇒x = 5.8/2.9

⇒ x = 2

Step 3 of 3

Now by putting the value of x in eq(1) we get

0.4*2 + 0.3y = 1.7

⇒0.3y = 1.7 - 0.8

⇒0.3y = 0.9

⇒ y = 3

Hence by solving the given equations by elimination method we get the values of x and y as 2 & 3 respectively.