Can you please refer Question no. 10 of exercise 8.1 in which I started the question by taking PR= 25 - QR and proceded correctly but I got the value of QR incorrect I don't understand what mistake I have made but can you solve it by taking PR's value as 25 - QR and apply the Pythagoras theorem in which P R to the power of 2 space end exponent equals space P Q squared space plus Q R squared and please take the value of PR as 25-QR?

Asked by Varsneya Srinivas | 19th Jul, 2015, 11:30: AM

Expert Answer:

C o n s i d e r space t h e space f o l l o w i n g space f i g u r e colon
L e t space Q R equals x G i v e n space t h a t space P R plus Q R equals 25 rightwards double arrow P R equals 25 minus x C o n s i d e r space t h e space r i g h t space t r i a n g l e space triangle P Q R colon B y space a p p l y i n g space P y t h a g o r a s space T h e o r e m comma space w e space h a v e comma P R squared plus Q R squared equals P R squared rightwards double arrow 5 squared plus x squared equals open parentheses 25 minus x close parentheses squared rightwards double arrow 5 squared plus x squared equals 625 plus x squared minus 50 x rightwards double arrow 25 plus x squared equals 625 plus x squared minus 50 x rightwards double arrow 0 equals 600 minus 50 x rightwards double arrow x equals 12 rightwards double arrow P R equals 25 minus 12 equals 13 C o n s i d e r sin P equals 12 over 13 semicolon space cos P equals 5 over 13 space a n d space tan P equals 12 over 5

Answered by Vimala Ramamurthy | 19th Jul, 2015, 05:15: PM