Use cosine rule,
cos(A)=(b^2+c^2-a^2)/(2bc)
=(10^2+12^2-6^2)/(2*10*12)
=13/15
A=29.926 degrees.................................(A)
cos(B)=(c^2+a^2-b^2)/(2ca)
=(12^2+6^2-10^2)/(2*12*6)
=5/9
B=56.251 degrees.................................(B)
cos(C)=(a^2+b^2-c^2)/(2ab)
=(6^2+10^2-12^2)/(2*6*10)
=-1/15
C=93.823 degrees.................................(C)
Check:29.926+56.251+93.823=180.0 degrees....ok
You have to multiply 3 times 2= 6 + 4 = 10 so the answer is 10 I hope this help...
Answer:
Janninne made 68% then 3/25 turned into percentage 12% then 0.2 equals 20%. So you order it by 68% (Janinee), 20% (Kathy), AND 12% (Monique)
Answer:
b) i) Curve A
ii) - 1.75
iii) x = 1 - √5 or x = 1 + √5
Step-by-step explanation:
b) i) We are given a function y = x² - 2x - 3 and the graph of this function is also shown in the side diagram.
The equation can be rearranged to y = (x - 1)² - 4
⇒ (x - 1)² = y + 4
Therefore, this is an equation of a parabola having the vertex at (1,-4) point and its axis is parallel to the positive y-axis.
So, the curve A represents the equation given. (Answer)
ii) Now, at x = 2.5, f(x) = 2.5² - 2 × 2.5 - 3 = - 1.75 (Answer)
iii) When y = 1, then x² -2x - 3 = 1
⇒ x² - 2x - 4 = 0
⇒ (x - 1)² - 5 = 0
⇒ (x - 1)² - (√5)² = 0
⇒ (x - 1 + √5)(x - 1 - √5) = 0
⇒ x = 1 - √5 or x = 1 + √5 (Answer)
Triangle B can be proven congruent
