Answer:
16.2
Step-by-step explanation:
The angle internal to the triangle at B is the supplement of the one shown, so is 65°. That is equal to the angle internal to the triangle at D. Since the vertical angles at C are congruent, the two triangles are similar by the AA theorem.
Corresponding sides of similar triangles are proportional, so we can write the proportion shown in the attachment:
BC/FC = DC/AC
BC = FC(DC/AC) = 21.6(7.2/9.6)
BC = 16.2 . . . . matches the first choice
Answer:
V≈461.81cm³
Step-by-step explanation:
Answer: A. contains a number and a unit
Step-by-step explanation:
Quantitative observations measure the quantity, or the amount, of a certain thing. Therefore they must always use a number value to measure the amounts, and a unit to signify what the amount is for.
Answer:
henc X = 30°
Step-by-step explanation:
here is the proof
when X=30° then
sin2x = sin2×30
=sin 60°
= √3/2
or else,
putting value of X = 30° then
sin2x= 2sinxcosx
= 2×sin30°×cos30°
=2×1/2×√3/2
= 2√3/4
= √3/2
hence proved sin2x= √3/2.
