This is a quadratic equation, i.e. an equation involving a polynomial of degree 2. To solve them, you must rearrange them first, so that all terms are on the same side, so we get

i.e. now we're looking for the roots of the polynomial. To find them, we can use the following formula:

where
is a compact way to indicate both solutions
and
, while
are the coefficients of the quadratic equation, i.e. we consider the polynomial
.
So, in your case, we have 
Plug those values into the formula to get

So, the two solutions are


a) As the constants are equal, the situation represents a proportional relationship.
b) The constant of 2/3 cupcakes per minute means that in a minute, 2/3 of a cupcake is made.
<h3>What is a proportional relationship?</h3>
A proportional relationship is a function in which the output variable is given by the input variable multiplied by a constant of proportionality, that is:
y = kx
In which k is the constant of proportionality.
In this problem, the constants for each situation are:
k = 30/45 = (30/15)/(45/15) = 2/3 = 20/30.
Since the constants are equal, the situation represents a proportional relationship.
The constant of 2/3 cupcakes per minute means that in a minute, 2/3 of a cupcake is made.
More can be learned about proportional relationships at brainly.com/question/10424180
#SPJ1
Complete question is attached.
Answer:
B) 8
Step-by-step explanation:
In this question, KLMN ~ PQRS. This means they are similar shapes.
From the image, we could denote that:
KL ~ PQ
LM ~ QR
Given that:
KL = 12
PQ = 30
QR = 20
LM = x
To find x, let's use tge expression:
Cross multiplying, we have:
12 * 20 = 30x
240 = 30x
To find x, let's divide both sides by 30.
8 = x
x = 8
The correct option is option B.