6x^2 - 8 = 4x^2 + 7x
6x^2 - 4x^2 - 7x - 8 = 0
2x^2 - 7x - 8 = 0
discriminant = b^2 - 4ac; where a = 2, b = -7 and c = -8
d = (-7)^2 - 4(2)(-8)
d = 49 + 64
d = 113
the discriminant is greater than zero, so there are two real roots
Answer:
tall candles = 39
Short candles = 52
Step-by-step explanation:
let tall candles be x
and short candles be y
No. Of candles sold = x + y =91
Money made from candles will be equal to = 8x + 5y = $572
These both are simultaneous linear equations.
x + y =91 ( multiply by 5)
5x + 5y = 455
8x + 5y = $572
Subtract them:
-3x = -117
x = -117/3
x = 39
put value of x in
x + y = 91
39 + y = 91
y = 91 - 39
y = 52
x shows tall candles so they are 39
y shows short candles so they are 52
ANSWER:
a = 11
b = 2
Explaination:
We have two equations:
a = 5b + 1 .....................(1)
a = 3b + 5.....................(2)
Here we use substitution method in order to solve the set of equations.
put a=3b+1 to equation (1)
3b + 5 = 5b + 1
Solve for b
5 = 5b -3b + 1
5-1 =2b
4 = 2b
b = 2
Now put the value of b = 2 into the equation (1) or (2)
a = 5b + 1
a = 5(2) + 1
a = 10 + 1
a = 11
Answer:
x - y = 3
any values of x& y where x is three greater than y
I.E. x = 8 y = 5
Step-by-step explanation:
