Katie and Margarita have $20.00 each to spend at Student Choice bookstore, where all students recieve a 20% discount. They both want to purchase a copy of the same book which normally sells for $22.50 plus 10% sales tax.
Write an expression to find the total cost of the book with tax and the discount.
Margarita wants to figure out if she has enough money. She finds 80% of the normal price and then computes 110% of the reduced price.
Is margarita correct? Will this give her the cost with tax and the discount? Explain.
Do they have enough money to purchase the book? How do you know?

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.

step-by-step explanation :

we know that

the measurement of the outer angle is the semi-difference of the arcs which comprises

in this problem

m< xzy is the outer angle

substitute the values

the measure of angle xoy is equal to

> by central angle

substitute the value

idk

step-by-step explanation: