How do I know if a pair is a function or not?

If cos θ = - 2/5 and tan θ > 0, what is the value of sin θ? Answer Choices: a) the negative square root of 21 b) the negative square root of 21 over 5 c) the square root of 21 over 5 d) the square root of 21 over 2

Determine the intercepts of the line. y + 5 = 2 (x + 1) y-intercept: x-intercept:

Suppose you have 10 marbles, They are marked with the numbers: 1,2,3,4,5,6,7,8,9 or 10. They are placed in a jar and you reach in and select one. What is the probability that the number you select has a factor of 3?.

The band has a banner at the back of the stage. It is 21 feet long. Approximately how many metres is this? m (A foot is about 30 cm.)

What is the exponential form of the following expression (-5) (-5) (-5) •c•c•c

Adante begins to evaluate the expression 3 and one-third times 5 and one-fourth using the steps below.

Joe buys a 4 1/2 pound bag of dog food every 4 weeks, joe feeds his song the same amount each day. What is the number of pounds the dog eats each year?

What is 6.78 and 8.21 rounded to tenth nearest tenth

A circle has diameter 11cm A square has side length 7cm Use Pythagoras' Theorem to show that the square will fit inside the circle without touching the edge of the circle.

Sally has six flowers three of the flowers are yellow. the rest are red. how many flowers are red