Answer:
I think it is C sorry if it wrong
Step-by-step explanation:
39 has factors (1 * 39) & (3 * 13)
Here we'll try
m + n = 13
m - n = 3
2m = 16
m = 8
2n = 10
n = 5
2mn = 2 * 8 * 5 = 80
So this choice is no good.
Let's go with
m + n = 39
m - n = 1
2m = 40
m = 20
2n = 38
n = 19
Thus
x = 20² - 19² = 39
y = 2 * 20 * 19 = 760
z = 20² + 19² = 761
Answer:
Step-by-step explanation:
<h3>Q13</h3>
The greater the angle the greater the opposite side
<u>Sides in ascending order:</u>
- AB = 17, AC = 18, BC = 21
<u>Angles in same order</u>
<h3>Q14</h3>
<u>As above, sides in ascending order:</u>
- AB = 15, AC = 16, BC = 17
<u>Angles in same order</u>
<h3>Q15</h3>
<u>Exterior angle equals to sum of non-adjacent interior angles</u>
- 142° = x + 66°
- x = 142° - 66°
- x = 76°
<h3>Q16</h3>
<u>Same subject and isosceles triangle:</u>
- x + x = 158°
- 2x = 158°
- x = 79°
<h3>Q17</h3>
<u>Same subject</u>
- m∠QSR = m∠QPS + m∠PQS
- 2x = x + m∠PQS
- m∠PQS = 2x - x
- m∠PQS = x
ΔPQS has two angles with the measure of x, hence their opposite sides are congruent and the triangle is isosceles
The common factor of 7 and 15 is 1