Answer:
x=1
y=-1
Step-by-step explanation:
they have already isolated y in both equations
label both equations
y=-x............1
y=3x-4........2
sub 1 into 2
-x=3x-4
-x-3x=-4
-4x=-4
x=1........ 3
sub 3 into 1
y=-(1)
y=-1
X + y = 20 Substitute
x by 2 y - 4 in x + y = 20 to obtain 2 y •
4 + y = 20 Solve for y to find y = 8 and
x = 2y - 4 = 12
Answer:the number is ten
Step-by-step explanation:
How many booths and tables are there altogether?