How to do this equation by elimination 8x 14y= 4 and -6 -7y =-10

Eliminate the y terms

multiply -6x-7y=-10 by 2 and add to other equaiation

8x+14y=4
-12x-14y=-20+
-4x+0y=-16

-4x=-16
divide both sides by -4
x=4
sub back

-6x-7y=-10
-6(4)-7y=-10
-24-7y=-10
add 24 o both sides
-7y=14
divide both sides by -7
y=-2

x=4
y=-2
(4,-2)

The lateral side of a triangular pyramid is a triangle. in order to increase the lateral surface area, the slant height and the height should be altered