Question

5x+7y=79,7x+5y=77solve the word problem

Answer 1

Hey mate
here is your answer

By Elimination method
We can solve this,
let 5x+7y=79 be equation 1
7x+5y=77 be equation 2

Now In order to cancel x variable,
◇ Multiply eqn 1 by 7
◇ Multiply eqn 2 by 5

So you will get
35x+49y=553
35x+25y=385
(-) sign change
____________
24y=168
____________

y=168/24
y=7

y=7 subs in eqn 1
5x+49=79
5x=30
x=6

Solution
x=6
y=7
same way you can cancel y variable too you get the same answer
hope this helps you :)

keep smiling

Answer 2

5x + 7y = 79 -----------------(1) equation
7x + 5y = 77 -----------------(2) equation
now add equation 1 & 2
12x + 12y = 156 now divide from 12
x + y = 13 --------------- (3) equation
multiply 5 in equation (3) and then substract to equation(1)
2y = 14 then y = 7
put this value in any one of the equation among three.
x + 7 = 13 then x = 6
x = 6 and y = 7