8x^2+6x^2+4x=138 combine like terms on left side
14x^2+4x=138 since the number of seats in the from row is just 4x, subtract 14x^2 from both sides
4x=138-14x^2 that would be the general solution, if you wanted the actual number you would have to solve for x and then multiply that value by 4 to know what "4x" is...
14x^2+4x-138=0
14x^2-42x+46x-138=0
14x(x-3)+46(x-3)=0
(14x+46)(x-3)=0
2(7x+23)(x-3)=0, since x>0
x=3 and thus
4x=12 seats
So there are 12 seats in the front row addition.
Answer:
t = d/S
Step-by-step explanation:
S = d/t
Cross multiply
S x t = d
Divide both sides by S
S/S x t = d/S
t = d/S
Answer:
$0.20 per candy bar
Step-by-step explanation:
There are 50 candy bars per box. It's costing the school $30/50=$0.60 per candy bar to buy. The school sells each candy bar for $0.80, making a profit of $0.20 per candy bar.
Answer:
53/10, 5 9/25 ; 5.81 ; 5.818
Step-by-step explanation:
To find the solution we need to make some calculations:
53/10 = 5.3
5 9/25 = 5.36
So we have that the solution is:
53/10, 5 9/25 ; 5.81 ; 5.818