Math, asked by maahira17, 8 months ago

Solve the following systems of equations:
0.5x + 0.7y = 0.74
0.3x + 0.5y = 0.5

Answers

Answered by nikitasingh79
2

Given pair of system of equation :  

0.5x + 0.7y = 0.74 …………...( 1 )

0.3x - 0.5y = 0.5 …………...( 2 )

On multiplying eq 1 & 2  both sides by 100 :  

50x + 70y = 74 ……….... (3)

30x + 50y = 50 ………... (4)

From eq (3) :  

50x = 74 - 70y

x = (74 - 70y)/50 …………(5)

On Substituting the value of x in equation (4) we get :  

30x + 50y = 50

30 (74 - 70y)/50 + 50y = 50

3(74 - 70y)/5 + 50y = 50

[(222 - 210y) + 250y]/5 = 50

[222 - 210y + 250y] = 50 × 5  

40y = 250 - 222

40y = 28

y = 28/40 = 7/10

y = 0.7

On putting the value of y in the equation (5) :  

x = (74 - 70y)/50

x = (74 - 70 × 0.7)/50

x = (74 - 49)/50

x = 25/50

x = 5/10

x = 0.5

Hence, the value of the given system of equation is x = 0.5   and y = 0.7.

Hope this answer will help you…

 

Some more similar questions from this chapter :  

Solve the following systems of equations:

0.4x + 0.3y = 1.7

0.7x - 0.2y = 0.8

https://brainly.in/question/17116587

 

Solve the following systems of equations:

3x - ( y + 7)/11 + 2 = 10  

2y + (x + 11)/7  = 10

https://brainly.in/question/17131588

Answered by Anonymous
2

Step-by-step explanation:

0.5 x +0.7 y = 0.74 (i)

multiply 10 on both sides in (i)

=> 5x+7y=7.4

0.3 x + 0.5 y =0.5 (ii) 

multiply 10 on both sides in (ii)

3 x + 5 y = 5 

y=1-0.6x (from ii equation)

Now, Substitute value in equation i

5x+7y = 5x + 7(1-0.6x)=7.4

=>5x +7-4.2x =7.4

=>0.8x+ 7 = 7.4

=>x=0.5

Now substitute x value in any equation. 

Let us take the second equation.

0.3x + 0.5y =0.5

(0.3×0.5)+0.5y= 0.5

0.3+y= 1

∴y=0.7

Hope my answer is helpful to u. Pls mark it the brainliest if u like.

Similar questions