22. The equation y = +9.8x +2 models the trajectory of a ball thrown in the air by a man, where y = the distance the ball is from the ground in meters and x = the elapsed time in seconds. What is the greatest distance the ball is from the ground?

A student's grade in a course is the average of 4 test grades and a final exam that is worth four times as much as each test. Suppose a student has test grades of 89, 88, 89, and 94. Write an equation to model this situation where xxis the student's grade on the final exam and yyis the student's average for the course.

Gold is alloyed with different metals to make it hard enough to be used in jewelry. The amount of gold present in a gold alloy is measured in 24ths called karats. 24-karat gold is 100% gold. Similarly, 18-karat gold is 75% gold. 
How many ounces of 14-karat gold should be added to an amount of 8-karat gold to make 6 ounces of 12-karat gold? Graph equation(s) on coordinate axes with labels and scales. *

Morgan's Mediterranean Restaurant has found that the number of falafel plates sold can be modeled by the equation y=1.8x+9.2y=1.8x+9.2 where xx  represents the number of years since 2015, and yy  represents the number of falafel plates sold, in thousands.   Predict the number of falafel plates the restaurant will sell in 2027. Incorrect   Predict the number of falafel plates the restaurant will sell in 2033.