Note necessary facts about isosceles triangle ABC:
- The median CD drawn to the base AB is also an altitude to tha base in isosceles triangle (CD⊥AB). This gives you that triangles ACD and BCD are congruent right triangles with hypotenuses AC and BC, respectively.
- The legs AB and BC of isosceles triangle ABC are congruent, AC=BC.
- Angles at the base AB are congruent, m∠A=m∠B=30°.
1. Consider right triangle ACD. The adjacent angle to the leg AD is 30°, so the hypotenuse AC is twice the opposite leg CD to the angle A.
AC=2CD.
2. Consider right triangle BCD. The adjacent angle to the leg BD is 30°, so the hypotenuse BC is twice the opposite leg CD to the angle B.
BC=2CD.
3. Find the perimeters of triangles ACD, BCD and ABC:



4. If sum of the perimeters of △ACD and △BCD is 20 cm more than the perimeter of △ABC, then

5. Since AC=BC=2CD, then the legs AC and BC of isosceles triangles have length 20 cm.
Answer: 20 cm.
<u>Answers</u>
19 fiction books
7 nonfiction books
<u>Explanation</u>
x + y = 26 ............................................. (i)
x – y = 12 ............................................ (ii)
Elliot added the two equations and the result was
2x = 38.
Dividing both sides by 2;
x = 19
There are 19 fiction books.
Substituting x in equation (i),
x + y = 26 when x = 19
19 + y = 26
y = 26 - 19
= 7
There are 7 nonfiction books
We know that
If a system has at least one solution, it is said to be consistent.
When you graph the equations, both equations represent the same line
so
the system has an infinite number of solutions
If a consistent system has an infinite number of solutions, it is dependent.
<span>
therefore
the system is </span>consistent, dependent and <span>equivalent
</span><span>
the answer is
</span>equivalent
Answer:
How many standard deviations above the mean is 14,500 hours? 1.25 1.5 2.5 Using the standard normal table, the probability that Seth's light bulb will last no more than 14,500 (P(z ≤ 1.25)) hours is about ✔ 89% .
Answer: cos(53o)=y/5
<span>T
riangle abc is a right triangle and sin(53o) = . solve for x and round to the nearest whole number. which equation correctly uses the value of x to represent the cosine of angle a?cos(53o) = 4/xcos(53o) = y/5cos(53o) = x/4cos(53o) = 5/y</span>