The perpendicular to parallels theorem proves that

a. alternate interior angles are congruent
b. congruent angles are equal
c. two lines are perpendicular
d. two lines are parallel

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).

What is negative 3/9 times negative 2/8 ?

Which best explains why this triangle is or is not a right triangle ?