Answer:
a) 5.83 cm
b) 34.45°
Step-by-step explanation:
a) From Pythagoras theorem of right triangles, given right triangle ABC:
AB² + BC² = AC²
Therefore:
AC² = 5² + 3²
AC² = 25 + 9 = 34
AC = √34
AC = 5.83 cm
b) From triangle ACD, AC = 5.83 cm, AD = 4 cm and ∠A = 90°.
From Pythagoras theorem of right triangles, given right triangle ACD:
AD² + AC² = DC²
Therefore:
DC² = 5.83² + 4²
DC² = 34 + 16 = 50
DC = √50
DC = 7.07 cm
Let ∠ACD be x. Therefore using sine rule:

Add the five to each side.
then square it to get rid of the square root
2x+13=(5+x)^2
2x+13=x^2+10x+25
2x=x^2+10x+12
x^2+8x+12=0
(x+6)(x+2)
x+6=0
x+2=0
answers are -2 and -6, however, when pluging -6 in it doesnt work, so it is only -2.
Answer: Sara multiplied by 3 when she should have multiplied by 8.
Step-by-step explanation:
21 : 7*8
7*8 = 56
21 : 56
The simplest form of this ratio is 3 : 8
Answer:
8.4*10^-3
Step-by-step explanation:
Move the decimal point 3 places in order to get a number in the one's place.