for these you need to rearrange the equations and do substitutions.
#3 = if x+y=5 then you know x = 5-y
now substitute that equation for x in the 2nd one so x + 2y = 8 becomes
5-y + 2y = 8 2y - y becomes 1y which becomes y then subtract 5 from each side to get y =3
now replace y with 3 in the first equation x = 5-3 so x = 2
so (2,3) is the answer
same type of work for #4
2x-y=6 ,S0 y = 2X+6
so now you have 4x+2(2x+6)=-4
that becomes 4x +4x+12 = -4
8x+8 = 1, x =1
y = 2(1)-6 = -4
so answer is (1,-4)
Answer:
1) x²+4x=2700
2) 50x50
Step-by-step explanation:
Pony area = x²
line-up area=4x
x²+4x=2700
x²+4x-2700=0
(x-50)(x+54)
So x= 50 or -54. Since it can’t be a negative number, it must be 50.
CHECK:
Square = 50x50 = 2500
Line up area = 50x4 = 200
2500+200=2700 YES