Top answers

You area told that y is proportional to x2 and that when y = 75, x = 5. a) Find a formula for y in terms of x. b) Find the value of y when x = 3. c) Find the value of x when y = 1200.

a) when y=75 x=5 and y is proportional to x^2, so the answer is y=___x^2 if x=5, then x^2 = 25, and 75/25=3, so the answer is y=3x^2 b) if x=3, x^2=9, if you multiply this by 3, you get the answer of 27. c)i...
MB
Answered by Millie B. • Maths tutor
3780 Views

Express 3cos(theta) + 5sin(theta) in the form Rcos(theta - alpha) where R and alpha are constants, R>0 and 0<alpha<90. Give the exact value of R and the value of alpha to 2dp.

Write out identity: Rcos(theta - alpha) = Rcos(theta)cos(alpha) + Rsin(theta)sin(alpha) from formula booklet Write out in form of question so it's easier to compare: 3cos(theta) + 5sin(theta) = R[cos(alpha)c...
OS
Answered by Olivia S. • Maths tutor
15653 Views

What is the difference between a Bronsted Lowry acid and a Lewis Acid?

In chemistry there are two distinct theories to explain acid-base reactions; the Bronsted-Lowry and Lewis acid-base theories. The Bronsted-Lowry theory talks about removal or transfer of hydrogen ions (H+) i...
ME
Answered by Michael E. • Chemistry tutor
46983 Views

how to write down the differential equation from a word problem, involving rate of change.

Read the word problem more than once to make sure you fully understand what is being asked and write down the variables involved. Then try to write down all the derivatives in terms of each other, using the ...
CG
3503 Views

How do you use position words in Mandarin?

Some position words: 前边 qián - in front 后边 hòu - behind 左边 zuǒ - left 右边 yòu - right 上边 shàng - above 下边 xià - below 里边 lĭ - inside 外边 wài - outside Explanation: Word order is different in Chinese from what ...
SC
Answered by Serena C. • Mandarin tutor
4220 Views