the marked angles are complementary → B
All 3 triangles are right with one angle = 90°
the sum of the angles in a triangle = 180°
thus the remaining 2 marked angles sum to 90°, thus are complementary
Answer:
tan(2u)=[4sqrt(21)]/[17]
Step-by-step explanation:
Let u=arcsin(0.4)
tan(2u)=sin(2u)/cos(2u)
tan(2u)=[2sin(u)cos(u)]/[cos^2(u)-sin^2(u)]
If u=arcsin(0.4), then sin(u)=0.4
By the Pythagorean Identity, cos^2(u)+sin^2(u)=1, we have cos^2(u)=1-sin^2(u)=1-(0.4)^2=1-0.16=0.84.
This also implies cos(u)=sqrt(0.84) since cosine is positive.
Plug in values:
tan(2u)=[2(0.4)(sqrt(0.84)]/[0.84-0.16]
tan(2u)=[2(0.4)(sqrt(0.84)]/[0.68]
tan(2u)=[(0.4)(sqrt(0.84)]/[0.34]
tan(2u)=[(40)(sqrt(0.84)]/[34]
tan(2u)=[(20)(sqrt(0.84)]/[17]
Note:
0.84=0.04(21)
So the principal square root of 0.04 is 0.2
Sqrt(0.84)=0.2sqrt(21).
tan(2u)=[(20)(0.2)(sqrt(21)]/[17]
tan(2u)=[(20)(2)sqrt(21)]/[170]
tan(2u)=[(2)(2)sqrt(21)]/[17]
tan(2u)=[4sqrt(21)]/[17]
Ngl I think it’s 20 because 15 is 5x3 but 60 divided by 3=20 lmk if I’m wrong
Answer:
x = 11
Step-by-step explanation:
3x - 7 = x + 15 ( subtract x from both sides )
2x - 7 = 15 ( add 7 to both sides )
2x = 22 ( divide both sides by 2 )
x = 11
One number: x
Its consecutive: x + 1
Product:
x(x+1)=121
x² + x - 121 = 0
Δ = 1² - 4.1.(-121)
Δ = 1+484
Δ = 485
As square root of 485 is not integer, do not exist two consecutive numbers with product of 121
