Help Maths THanks + Rep to all that help

[Galaxay1]

BowTies try quad formula?

-b + Square root of x(squared)-4AC
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2a

[BowTies1]

whats the formul;a in your calculater you put for calculating compound intrest fast isntead of going threw year 1 year 2 year 3 etcetc


yhe question is what is the fare price of the fare galsgow to london(26£ ) in 10 years if it rises by 2% per year

[Galaxay1]

26x1.02 to the power of 10

[H]

solve each of these equations 1. 6x(squared) + x -12 = 0 b ) x(x-5)=84 c) (3x-4)(x-4)=-5
F) 5t(squared = 11t + 7 ( to 1dp)
-----------------------------------------------------
6x(squared) + x -12 = 0
x = 1.3 recurring
x = -1.5
----------------------------------------------------
x(x-5)=84
x squared - 5x - 84
x = -7
x = 12
----------------------------------------------------
(3x-4)(x-4)=-5
4x squared -16x + 16 = -5
4x squared - 16x + 11
x =
x =

(my calculator just died soz!)

[sierk1]

im struggling x(x-5) = 84 :S my next line of working i put

x(squared) - 5x - 84= 0 then i tried to facotrise but coudnt get it helop ?

That is not so hard, since 84=12x7 (as you are of course well aware).
So x^2-5x-84=0 becomes (x-12)(x+7)=0 (hence x=12 or x=-7 as solution).