SAT MATH Section 3

Which of the following is an equation of line A in the xy-plane above?

• x=1

• y=1

• y=x

• y=x+1

The circle above with center O has a circumference of 36. What is the length of minor arc AC ?

• 9

• 12

• 18

• 36

What are the solutions of the quadratic equation  $4x^2-8x-12=0$  

• -1 and -3

• -1 and 3

• 1 and -3

• 1 and 3

Which of the following is an example of a function whose graph in the xy-plane has no x-intercepts?

• A linear function whose rate of change is not zero

• A quadratic function with real zeros

• A quadratic function with no real zeros

• A cubic polynomial with at least one real zero

 $\sqrt{k+2}-x=0$  
In the equation above, k is a constant. If x=9, what is the value of k?

• 1

• 7

• 16

• 79

Which of the following is equivalent to the sum of the expressions  $a^2-1$  and  $a+1$  ?

•  $a^2+a$  

•  $a^3-1$  

•  $2a^2$  

•  $a^3$  

Jackie has two summer jobs. She works as a tutor, which pays $12 per hour, and she works as a lifeguard, which pays $9.50 per hour. She can work no more than 20 hours per week, but she wants to earn at least $220 per week. Which of the following systems of inequalities represents this situation in terms of x and y, where x is the number of hours she tutors and y is the number of hours she works as a lifeguard?

• $12x+9.5y\le220$ $x+y\ge20$

• $12x+9.5y\le220$ $x+y\le20$

• $12x+9.5y\ge220$ $x+y\le20$

• $12x+9.5y\ge220$ $x+y\ge20$

In air, the speed of sound S, in meters per second, is a linear function of the air temperature T, in degrees Celsius, and is given by S(T)=0.6T+331.4.

Which of the following statements is the best interpretation of the number 331.4 in this context?

• The speed of sound, in meters per second, at 0°C

• The speed of sound, in meters per second, at 0.6°C

• The increase in the speed of sound, in meters per second, that corresponds to an increase of 1°C

• The increase in the speed of sound, in meters per second, that corresponds to an increase of 0.6°C

If (x;y) is a solution of the system of equations above and x>0, what is the value of xy ?

• 1

• 2

• 3

• 9

• A

• B

• C

• D