Let c and d be the number of cds and dvds respectively.
c+d=12
c=12-d
The we are told that:
2c+3d=31, using c found above in this equation gives you:
2(12-d)+3d=31
24-2d+3d=31
24+d=31
d=7
So Phillip bought 7 dvds.
check...
3*7+2(12-7)=31
21+2(5)=31
21+10=31
31=31
Rhombus, <span>opposite angles are congruent
One angle is 35 so the opposite angle will be 35 also.
Sum of interior angles in a rhombus equal 360
360 - 35 - 35 = 290
290/2 = 145 (The other two angles will be congruent)
Answer:
The remaining three angles will be 35</span>°<span>, 145</span>°<span>, 145</span>°<span>
</span>
Hello!
6.
Since the area is that of a square, you know that all side lengths are the same.
Area is base times height (A = bh), but since base and height are the same for a square, you get the formula A = a².




The length of the side of a square with an area of 144 in² is
12 in.
7.
Rational number.
8.
This is a right triangle; use the Pythagorean Theorem to find missing lengths of right triangles. Pythagorean Theorem: a² + b² = c², where c is the hypotenuse of the triangle.
Plug in your leg lengths:
a² + b² = c²
8² + x² = 21²
64 + x² = 441
x² = 377
x = 19.4
Answer:
$840
Step-by-step explanation:
First, add 30 to 10.
Then, multiply your answer (40) by 21.
Finally, you get your final answer of $840.