Question

if the equations X + 5 Y= 7 and 4 x + 20 Y= -K represent coinciding straight lines then the value of k is​

Answer 1

multiply first line by 4

we get

4x+ 20y = 28

but second line

4x+20y = -k

given they are coincide

-k =28

k = -28

Answer 2

k=28

x+5y-7=0

4x+20y+k

then

elimition mathed use

find x=