#1)
A) b = 10.57
B) a = 22.66; the different methods are shown below.
#2)
A) Let a = the side opposite the 15° angle; a = 1.35.
Let B = the angle opposite the side marked 4; m∠B = 50.07°.
Let C = the angle opposite the side marked 3; m∠C = 114.93°.
B) b = 10.77
m∠A = 83°
a = 15.11
Explanation
#1)
A) We know that the sine ratio is opposite/hypotenuse. The side opposite the 25° angle is b, and the hypotenuse is 25:
sin 25 = b/25
Multiply both sides by 25:
25*sin 25 = (b/25)*25
25*sin 25 = b
10.57 = b
B) The first way we can find a is using the Pythagorean theorem. In Part A above, we found the length of b, the other leg of the triangle, and we know the measure of the hypotenuse:
a²+(10.57)² = 25²
a²+111.7249 = 625
Subtract 111.7249 from both sides:
a²+111.7249 - 111.7249 = 625 - 111.7249
a² = 513.2751
Take the square root of both sides:
√a² = √513.2751
a = 22.66
The second way is using the cosine ratio, adjacent/hypotenuse. Side a is adjacent to the 25° angle, and the hypotenuse is 25:
cos 25 = a/25
Multiply both sides by 25:
25*cos 25 = (a/25)*25
25*cos 25 = a
22.66 = a
The third way is using the other angle. First, find the measure of angle A by subtracting the other two angles from 180:
m∠A = 180-(90+25) = 180-115 = 65°
Side a is opposite ∠A; opposite/hypotenuse is the sine ratio:
a/25 = sin 65
Multiply both sides by 25:
(a/25)*25 = 25*sin 65
a = 25*sin 65
a = 22.66
#2)
A) Let side a be the one across from the 15° angle. This would make the 15° angle ∠A. We will define b as the side marked 4 and c as the side marked 3. We will use the law of cosines:
a² = b²+c²-2bc cos A
a² = 4²+3²-2(4)(3)cos 15
a² = 16+9-24cos 15
a² = 25-24cos 15
a² = 1.82
Take the square root of both sides:
√a² = √1.82
a = 1.35
Use the law of sines to find m∠B:
sin A/a = sin B/b
sin 15/1.35 = sin B/4
Cross multiply:
4*sin 15 = 1.35*sin B
Divide both sides by 1.35:
(4*sin 15)/1.35 = (1.35*sin B)/1.35
(4*sin 15)/1.35 = sin B
Take the inverse sine of both sides:
sin⁻¹((4*sin 15)/1.35) = sin⁻¹(sin B)
50.07 = B
Subtract both known angles from 180 to find m∠C:
180-(15+50.07) = 180-65.07 = 114.93°
B) Use the law of sines to find side b:
sin C/c = sin B/b
sin 52/12 = sin 45/b
Cross multiply:
b*sin 52 = 12*sin 45
Divide both sides by sin 52:
(b*sin 52)/(sin 52) = (12*sin 45)/(sin 52)
b = 10.77
Find m∠A by subtracting both known angles from 180:
180-(52+45) = 180-97 = 83°
Use the law of sines to find side a:
sin C/c = sin A/a
sin 52/12 = sin 83/a
Cross multiply:
a*sin 52 = 12*sin 83
Divide both sides by sin 52:
(a*sin 52)/(sin 52) = (12*sin 83)/(sin 52)
a = 15.11
Answer:
4.2
Step-by-step explanation:
closest to what I counted 3
Answer:
u = (-21)/20
Step-by-step explanation:
Solve for u:
u + 1/4 = (-4)/5
Put each term in u + 1/4 over the common denominator 4: u + 1/4 = (4 u)/4 + 1/4:
(4 u)/4 + 1/4 = -4/5
(4 u)/4 + 1/4 = (4 u + 1)/4:
1/4 (4 u + 1) = -4/5
Multiply both sides of (4 u + 1)/4 = (-4)/5 by 4:
(4 (4 u + 1))/4 = (-4)/5×4
4×(-4)/5 = (4 (-4))/5:
(4 (4 u + 1))/4 = (-4×4)/5
(4 (4 u + 1))/4 = 4/4×(4 u + 1) = 4 u + 1:
4 u + 1 = (-4×4)/5
4 (-4) = -16:
4 u + 1 = (-16)/5
Subtract 1 from both sides:
4 u + (1 - 1) = (-16)/5 - 1
1 - 1 = 0:
4 u = (-16)/5 - 1
Put (-16)/5 - 1 over the common denominator 5. (-16)/5 - 1 = (-16)/5 - 5/5:
4 u = (-16)/5 - 5/5
-16/5 - 5/5 = (-16 - 5)/5:
4 u = (-16 - 5)/5
-16 - 5 = -21:
4 u = (-21)/5
Divide both sides by 4:
u = ((-21)/4)/5
5×4 = 20:
Answer: u = (-21)/20
Answer: i think it is 8.93
Step-by-step explanation:
Answer:
f(x)=3-4 In (x-2)=graph 3
f(x)=3-In x=graph 1
f(x)=In (x+1)=graph 4
f(x)= 2In (x+3)= graph 2
Step-by-step explanation:
Use a graph tool to visualize the functions.Attached are the graphed functions respectively.
