Ms. Rodriguez is comparing prices between two different suppliers of math books. . Loughridge Publishing charges $100 for delivery and $15 per book.
• Boulware Books charges $400 for delivery and $10 per book.
How many books must be purchased for Boulware's Books to be the less expensive option?

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.

answer: it is a.,b.,d.

step-by-step explanation: