Question

. Find the value of (x+y) and (x-y) if 7x+4y=43 and 4x+7y=34​

Answer 1

Answer:

x+y=7

x-y=3

Step-by-step explanation:

Let 7x+4y=43 be equation 1

and 4x+7y=34 be equation 2

So adding 1 and 2 we have

11x+11y=77

simplifying the equation we have

x+y=7 ____________(3)

now subtracting 2 from 1 we have

3x-3y=9

simplifying the equation we have

x-y=3____________(4)

there you have the answer as equation 3&4