49x^2 - 9 = 0
As there is no x term, we can pretty much guess we have a situation where we factlrise by something known aa difference of two squares, so to factorise it:
49 = 7^2
9 = 3^2
x^2 = (x)^2
so...
(7x - 3)(7x + 3) = 0
7x - 3 = 0 7x + 3 = 0
x = 3/7 x = -3/7
Answer:
[-5, 2]
Step-by-step explanation:
We have to find the interval for which f(x) <= 0, the interval is [-5, 2].
The product of 4 and 5 is 20.
The problem above uses the concept of ratio and proportion. The ratio between the cost and amount of the organic milk should always be equal. The proportion between two cases is shown below,
($2.52 / 0.5 gallon) = (x / 4 gallons)
Solving for x gives x = 20.16. Therefore, 4 gallons of organic milk costs $20.16.
