Please solve q 35? Actually I can't understand the step that is tick marked

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1 Answer
Mar 22, 2018

See a process below...

Explanation:

Given are two equations..

color(blue)(a sec theta+btan theta+c=0" "circ1

color(blue)(p sec theta+qtan theta+r=0" "circ2

Multiply p to first equation (elimination method)

color(green)(ap sec theta+bptan theta+cp=0" "circ3

Multiply a to second equation...
color(green)(pa sec theta+qatan theta+ra=0" "circ4

Subtract circ4 from circ3...
We get
tantheta=(ar-cp)/(bp-aq)

Similarly find value of sectheta

Using sec^2theta-tan^2theta=1 it can be solved...

Since it's already in the pic in question.. I'm leaving it....