To get a B in a course, you must have an average of at least 80 points for 4 tests of 100 points each. For the first 3 tests, your scores are 79, 84, and 83. What must you score on the fourth test to earn an 80% average for the course?
points

step-by-step explanation:

answer: 2x + 2 − 2 = 10 − 2; subtraction property of equality

step-by-step explanation:

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.