Question

If 2x+4y=20 and 4x+2y=10, what is the value of x+y
plz tell right answer​

Answer 1

$\sf\huge\bold{\underline{\underline{{Solution}}}}$

To Find : value of x+y

Above given Equation can be solved by elimination method:

=>2x+4y=20-----(×4)

=>4x+2y=10------(×2)

New Equation obtained:

=>8x+16y=80

=>8x+4y=20

=>$\:(-)\:(-)\:(-)$

_____________

-12y=60

y=-60/12

y= -5

Now put y's value into this equation

=>2x+4y=20

=>2x+4×-5=20

=>2x-20=20

=>2x=20+20=40

=>2x=40

=>x=40÷2=20

x=20

Check

=>2x+4y=20

=>2×20+4×-5

=>40-20=20✓

Now, we have to find value of x + y

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$=>20+(-5)

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$=>20-5

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$=15

Extra information=>

Elimination method is a way of eliminating one variable from equation of two variable so that we can find value of one variable.

Elimination means =>To Remove

Method step by step For Elimination Method :

step 1: Firstly Multiply with any non-zero value so that the coefficient of any one variable of both the terms be equal and gets eliminated.

Generally we multiply with coefficient of a variable of both equation to each term.

step2: After Put negative sign where value is positive and put positive sign where value is negative so that any one variable gets eliminated or subtracted and hence we find value of any one variable.

step3: Now,after finding value of one variable substitute it another equation.

Answer 2

Answer:

5

Step-by-step explanation:

2x+4y=20 equation first and 4x+2y=10equation second