Let cheese wafers = x
chocolate wafers = y
we know they bought 20 total packets so x+y = 20, this can be re-written as x = 20-y
cheese wafers cost 2, so we have 2x
chocolate wafers cost 1, so we have 1y, which is just the letter y
so we know 2x + y = $25
replace x with x=20-y to get:
2(20-y)+y = 25
distribute the parenthesis:
40-2y +y = 25
combine like to terms to get:
40-y = 25
subtract 40 from each side"
-y = -15
divide both sides by -1
y = 15
chocolate wafers was y so they bought 15 chocolate wafers
cheese wafers was x, so they bought 20-15 = 5 cheese wafers
using the substitution method was the easiest way to isolate one of the variables in order to find the solution.
Answer:
(x+5i)(x-5i)
Step-by-step explanation:
We use imaginary numbers to solve that. since i = sqare root of -1 so i * i = -1.
I got 73.7460555 not rounded
Answer: according to spark notes: There can be 0, 1, or 2 solutions to a quadratic equation, depending on whether the expression inside the square root sign, (b2 - 4ac), is positive, negative, or zero. This expression has a special name: the discriminant.
In this case it is 0, not 2, which was my first and wrong answer
4/20 is 0.20, which is equivalent to 20%.
Remember that 1.0=100%, 0.5=50%, 0.2=20%, 0.05=5%, and so on.