Question

Questions attached help please

Answer 1

For 1 you should do it using substitution of simultaneous equations. You know that xy = 40 so work out what x or y is on it's own. (ie x = 40/y). Then put that into the equation x^2 + y^2 = 200, where x is now 40/y. Find out what y is, then work out x and put both into the final equation.

Answer 2

For 4, if you call Tariq, T and Jamil, J then put them into equations. So T = 2J. Then (T+1)+(J+1)= 86. Adding one onto T and J because both have got older by a year. So T + J = 84 and T = 2J, then you can put 2J into the first equation in place of T. So 2J + J = 84. So J = 28. And J this year is J+1 so 29 in the answer.

Answer 3

\[for (1)\left( x-y \right)^{2}=x ^{2}+y ^{2}-2xy=200-2*40=120\]
for (2) 3510*100/83
for (3) -++--++--++--++-- .......
we see number of positive terms=(101-1)/2=50
for (4) Let age of Jamil=x years
Then age of Tariq =2x years
by the question
(x+1)+(2x+1)=86
3x=84
x=84/3=28
age of Jamil=28+1=29 years
age of Tariq=28*2+1=57 years
for (5)
305 terms=(101*3+2) terms
\[-3,0,6,-3,0, 6, -3,0 ,6,......\]
\[\sum=\left( -3+0+6 \right)+\left( -3+0+6 \right)+101 \times+\left( -3+0 \right)\]
=3+3+3+...101 times-3
=3*101+(-3)=303-3=300

Answer 4

Thanks man :)