Question

pls help with Q-9 it is urgent

Answer 1

hello friend!!
here u go!
no of one rupee coin= x
no of 50 paise coins= y
it is given that no of 50 paise coins is double the number of one rupee coins
therefore,
y=2x
y-2x=0 .........................(eq1)
it is also given that the total amount of money is 30
now we shud find the total amount made with 50 paise/ 0.5 rupee coins
=0,5y
and total money with 1 rupee=1x=x
therefore, 
x+0.5y=30
x+1/2y=30
2x+y=60
y+2x=60....................(eq 2)
from eq 1 and 2
by substitution method
−2x+y=0;2x+y=60Step: Solve−2x+y=0for y:−2x+y+2x=0+2x(Add 2x to both sides)y=2xStep: Substitute2xforyin2x+y=60:2x+y=602x+2x=604x=60(Simplify both sides of the equation)4x4=604(Divide both sides by 4)x=15Step: Substitute15forxiny=2x:y=2xy=(2)(15)y=30(Simplify both sides of the equation)Answer:x=15 and y=30
one rupee=15
150 paise=30
plz mark as brainliest