Answer:
20
Step-by-step explanation:
x - 9 = 11
+9 +9
x = 20
The longest two sides will be 4 each and the shortest two sides will be 2 each
1. Answer (D). By the law of sines, we have
in any 
2. Answer (C). The law of cosines,
accepts up to three sides and an angle as an input.
3. Answer (D). Although this triangle is right, we are not given enough information to uniquely determine its sides and angles - here, we need either one more side or one more angle.
4. Answer (D). Don't get tripped up by answer choice (C) - this is just a rearrangement of the statement of the law of cosines. In choice (D), the signs of
and
are reversed.
5. Answer (B). By the law of sines, we have
Solving gives
Note that this is the <em>ambiguous (SSA) case</em> of the law of sines, where the given measures could specify one triangle, two triangles, or none at all!
6. Answer (A). Since we know all three sides and none of the angles, starting with the law of sines will not help, so we begin with the law of cosines to find one angle; from there, we can use the law of sines to find the remaining angles.
Answer:
B. r + l = 45; 2r + 3l = 96
39 regular; 6 long-distance
Step-by-step explanation:
There were 45 baskets, so
(1) r + l = 45
There were 96 points in the game, so
(2) 2r + 3l = 96
Solve equation (1) for l
l = 45 – r Substitute the value for l in Equation (2)
2r + 3(45 – r) = 96 Remove parentheses
2r + 135 - 3r = 96 Combine like terms
-r + 135 = 96 Subtract 135 from each side
-r = -39 Multiply each side by -1
r = 39 Substitute the value of r in Equation (1)
39 + l = 45 Subtract 39 from each side
l = 6
===============
Check:
(1) 39 + 6 = 45
45 = 45
(2) 2×39 + 3×6 = 96
78 + 18 = 96
96 = 96