7.2 HW

7-15. Copy the triangles at right. Homework Help ✎
a. Label the missing sides with their exact lengths. That is, leave
your answers in radical form.
b. The 30° − 60° − 90° triangle is sometimes called a half-equilateral triangle. Draw a picture
to illustrate this, and explain how that fact can be used to help label the missing sides in part
(a).

7-16. Find the measure of angle A in the diagram below. Homework Help ✎


7-17. Find the x- and y- intercepts of the quadratic function y = 2x2 + x − 10. Homework Help ✎

7-18. Evaluate each expression without using a calculator or changing the form of the
expression. Homework Help ✎
a.
b.
c.
d.

log(1)
log(103)
10log(4)
103log(4)
7-22. Find the value of x. Homework Help ✎
b.
a.

7-23. Solve the system of equations shown below. Homework Help ✎
x + y + z = 40
y=x−5
x = 2z

7-24. What is the domain of the entire graph of h(θ) = sinθ? Justify your reasoning. Homework
Help ✎

7-25. Antonio’s friend Jessica was also on The Screamer when it broke. Her seat was 65 feet
above the ground. What was her seat’s angle of rotation? Is there more than one
possibility? Homework Help ✎

7-26. Hilda was working on her homework. She completed the square to change y = 3x2 − 24x +
55 to graphing form in order to identify the vertex of the parabola. She did the work below and
identified the vertex to be (4, 39). When she got back to class and checked her answers, she
discovered that the vertex she found is incorrect, but she cannot find her mistake. Examine Hilda’s
work and explain to her what she did wrong. Then show her how to complete the square correctly
and identify the vertex. Homework Help ✎
y = 3x2 − 24x + 55
y = 3(x2 − 8x) + 55
y = 3(x2 − 8x + 16) + 55 −16
y = 3(x − 4)2 + 39