Question

0.7x -0.3y=1 and 1.25x=4 +y/6 solve for x and y​

Answer 1

Step-by-step explanation:

Given:-

0.7x -0.3y=1 and 1.25x=4 +y/6

To find:-

Solve x and y?

Solution:-

Given equations are 0.7x - 0.3y = 1------(1)

and 1.25x = 4+ y/6

=>1.25x=(24+y)/6

=>1.25x(6)=24+y

=>7.5x=24+y

=>7.5x-24 =y

Therefore, y = 7.5x -24 -------(2)

On Substituting the value of y in (1) then

=>0.7x - 0.3(7.5x-24) = 1

=>0.7x-2.25x+7.2 = 1

=>-1.55x+7.2=1

=> -1.55x = 1-7.2

=>- 1.55x = -6.2

=>1.55x=6.2

=>(155x/100)=62/10

=>155x/10=62

=>155x=62×10

=>155x=620

=>x=620/155

=>x=4

The value of x=4

On Substituting the value of x in (2)

=>y =7.5(4)-24

=>y=30-24

=>y=6

The value of y=6

Answer:-

x=4

y=6

Solution for the given problem is (4,6)

Check:-

LHS in Equation (1)

0.7(4)-0.3(6)

=>2.8-1.8

=1

LHS=RHS

LHS in second Equation

1.25(4)=5

RHS:-

4+(6/6)

4+1

=5

LHS =RHS is true for x=4 and y=6

Used method:-

• Substitution method