Question

If A=(6i-8j) units, B=(8i-3j) units, and C=(26i-19j), determine a and b such that aA+bB+cC=0 .....plz show the working clearly...drop a picture if u can...

Answer 1

Value of a , b so that aA + bB + C = 0 is a = -1.613 and b = 2.04

• That is since c is not given I am assuming it to be 1.

• aA + bB = - C

• a(6i - 8j) + b(8i -3j) = -26i + 19j

equating all is and js,

• 6a + 8b = -26 ==> (3a + 4b = -13)x8 = 24a + 32b = -104---(1)

• -8a + -3b = 19==> (8a + 3b = -19)x 3 = 24a + 9b = -57---(2)

equation (1) - (2) ==>

• 23b = -47===>
• b = -47/23 = - 2.04

from (1)

• a = (-13 - 4b)/3 = (-13 + 4x47/23)/3 = (-598 + 604)/(23x3) = -1.613