18 / 1 = x / 15......18 miles to 1 gallon = x miles to 15 gallon
cross multiply
(1)(x) = (18)(15)
x = 270 miles
Step-by-step explanation:
in ten minutes it goes 1 km in 60 minutes it goes 4 km
Answer:
46 degrees.
Step-by-step explanation:
Sin(angle) = 5/7. Using a calculator, this angle is thus 45.6, or approximately 46 degrees.
Answer:
x=13
Step-by-step explanation:
if you will substitute the value of f(x) with 5, you will get the following equation:
5=2x-21
2x=26/÷2
x=13
(I didn't know what you ment when you wrote x2, is it x square or 2X)
I really hope it was the second one, cause that's how I solved it.
The general form of a quadratic (second degree) equation is
, where
is called the Discriminant.
The Discriminant determines how many roots the equation will have as follows:
i) if D>0, the equation has 2 roots.
ii) if D=0, the equation has 1 double root.
iii) if D<0, the equation has no roots.
In our equation,
, a=1, b=-5, c=7
so the discriminant is D=(-5)^2-4*1*7=25-28<0
Thus the equation has no roots.
Remark: the equation has no roots in the Real numbers, but it has 2 roots in a larger set of numbers to be discussed in the future, the Complex numbers.