Just get a calculator and do 18 divide by 4
A) 4a - 3b + 2c
4(2, -1, 5) - 3(4, 3 , -2) + 2(5, 4, 0) = (8, -4, 20) - (12, 9, - 6) + (10, 8, 0) =
= (8 - 12 + 10 , -4 - 9 + 8 , 20 + 6 + 0) = (6, - 5, 26)
Answer: (6, - 5, 26)
b) magnitude of vector b

c) vector of length 7 parallel to vector c
=> m(5,4,0) = (5m,4m,0)
=>

=> m = 7 / √41 ≈ 1.093
=> 1.093 (5, 4, 0) = (5.465 , 4.372, 0)
Answer: (5.465 , 4.372 , 0)
Answer:
yes it is right but you might want to make it neater
Step-by-step explanation:
:)
Answer:
m<ABC = 71°
Step-by-step explanation:
Given:
m<BCA = 71°
x = 31 cm
y = 50 cm
Required:
m<ABC
Solution:
First, find AB, using Cosine Rule:
AB² = x² + y² - 2xy*Cos m<ABC
Plug in the values
AB² = 31² + 50² - 2(31)(50)*cos 71
AB² = 3,461 - 1,009.26128
AB² = 2,451.73872
AB = √2,451.73872
AB = 49.5150353 ≈ 50 cm
✔️Since AB ≈ 50 cm, and AC is also 50 cm, it means the triangle is an isosceles triangle.
Therefore, the base angles of ∆ABC, <ABC and <BCA, would be congruent.
Therefore,
m<BCA = m<ABC = 71°
m<ABC = 71°
Please click above answer