Sunday

January 25, 2015

January 25, 2015

Posted by **Anonymous** on Tuesday, September 17, 2013 at 11:22pm.

- Trig -
**Reiny**, Wednesday, September 18, 2013 at 12:22ammake quick sketches of right-angled triangles for each of the two cases, and use Pythagoras to find the missing sides.

first triangle:

since sinA = 12/13 , y = 12 and r = 13

x^2 + y^2 = r^2

x^2 + 144 = 169

x^2 = 25

x = ±5, but we are in quad II, so x = -5

then tanA = - 12/5

2nd triangle:

since tanB = -4/3

tan(A-B) = (tanA - tanB)/(1 + tanAtanB)

= (-12/5 - (-4/3) )/( 1 + (-12/5)(-4/3)

= (-16/15) / (21/5)

= -16/63

- Trig -
**TeeKay**, Wednesday, October 15, 2014 at 2:45pmAre you sure it's negative?

**Answer this Question**

**Related Questions**

trig - Let sin A = 12/13 with 90º≤A≤180º and tan B = -4/3 with 270...

Math - Let sin A = 12/13 with 90º≤A≤180º and tan B = -4/3 with 270...

algebra 1 help please - 4) a student score is 83 and 91 on her first two quizzes...

Trig - Suppose sin A = 12/13 with 90º≤A≤180º. Suppose also that sin ...

Trigonometry - Suppose sin A = 12/13 with 90º≤A≤180º. Suppose also ...

Algebra 2 - Solve. 4a-2≤a+1≤3a+4 4a-2-1≤a+1-1≤3a+4-1 4a-...

Math (Trigonometry) - 1. If sec x + tan x = 3/2 and 0 ≤ x ≤ pi/2 ...

Trig - Suppose sinA = 12/13 with 90º≤A≤180º. Suppose also that sinB...

Probability - Random variables X and Y are distributed according to the joint ...

probability - Random variables X and Y are distributed according to the joint ...