11) Since the triangle has a pair of congruent base angles, it is an isosceles triangle which means that the two pairs of legs are congruent.
Make them equal to each other in an equation.
5x = x + 20
Subtract x from both sides.
4x = 20
Divide both sides by 4.
x = 5
12) The two legs are congruent so that means the base angles must be congruent. First find the measure of the base angles. Create an equation:
x + x + 50 = 180
Combine like terms.
2x + 50 = 180
Subtract 50 from both sides.
2x = 130
Divide both sides by 2.
x = 65
Now make the base angle plus x equal 180, because they form a straight line.
65 + x = 180
Subtract 65 from both sides.
x = 115
13) You know the vertex angle (top angle) is 90 degrees because it is supplementary to a right angle. The triangle is isosceles because the two legs are congruent, so make the base angles plus 90 add up to 180 in an equation.
x + x + 90 = 180
Combine like terms.
2x + 90 = 180
Subtract 90 from both sides.
2x = 90
Divide both sides by 2.
x = 45
Find the median first. The middle of all the numbers.
5, 7, 8, 10, 11, 13, 14, 18, 27
11 is the median.
Then find the median of the upper quartile.
The upper quartile consists of numbers...
5, 7, 8, 10
Since it is an even set of numbers add the two in the middle and divided by two. So 7 plus 8= 15/2.
7.5 is your upper quartile.
1/9 is equal to 0.11, and 2/9 is equal to 0.22. You can see the pattern here, if you look at the numerator of the fraction and the decimal.
b ≤ 9 (b is less than or equal to 9)
Hope this helps! ;)