+0  
 
+1
126
11
avatar

https://vle.mathswatch.co.uk/images/questions/question17507.png

https://vle.mathswatch.co.uk/images/questions/question17660.png

https://vle.mathswatch.co.uk/images/questions/question17547.png

 May 4, 2020
 #1
avatar+171 
+1

Question 1

a) Substitute the \(x-y\)  as \(3\)

 \(5 \cdot 3 = \boxed{15}\)

b) \(2(x-y)=2 \cdot 3=\boxed{6}\)

c) Multiply \(x-y=3\) by \(-1\) to get \(-x+y=-3\) which equals \(y-x=\boxed{-3}\)

 May 4, 2020
 #2
avatar+171 
+1

Question 2

\(f(x)=x^2 - x^3\) is just a function, thus we can substitute \(-2\) into every \(x\).

Doing so we get \(f(-2)=(-2)^2-(-2)^3\) which equals \(f(-2)=4+8=\boxed{12}\)

Therefore the answer is \(\boxed{D}\)

 May 4, 2020
 #3
avatar
+1

p;lz can you help me po this ine https://vle.mathswatch.co.uk/images/questions/question17843.png

Guest May 4, 2020
 #4
avatar+171 
+1

Question 3

Know that \(pressure=\frac{force}{area}\), we can just substitute our known values into the equation.

The problem tells us that \(pressure=\frac{18N}{m^2}\) and \(area=4m^2\), thus we get \(\frac{18N}{m^2}=\frac{force}{4m^2}\).

Let's assume \(f\) as force. Cross multiplying we get \((f)m^2=18N \cdot 4m^2\).

Cancelling the \(m^2\), we get we get \(f=\boxed{72N}\).

Therefore the answer is \(\boxed{A}\)

 May 4, 2020
 #5
avatar
+1

thank you for helping i really appreciate it thnx

Guest May 4, 2020
 #7
avatar+171 
+1

Your welcome.

HannibalBarca  May 4, 2020
 #6
avatar+171 
+1

For this one https://vle.mathswatch.co.uk/images/questions/question17843.png

 

a) 

(i) \(\boxed{x=6, y=9}\)

(ii) To get the greatest possible value for \(3x-2y\), we have to have the greatest number for \(x\) and the least number for \(y\)

Therefore, \(x=10\) and \(y=5\) to get \(\boxed{20}\)

(iii) Similarly \(x=5\) and \(y=10\) to get \(\boxed{-5}\)

 

b)

Substituting the variables in, we get \(\boxed{-40}\)

 May 4, 2020
 #9
avatar
0

https://vle.mathswatch.co.uk/images/questions/question17117.png 

question b do you do 1.5x3=4.5

Guest May 4, 2020
 #8
avatar+171 
0

Any more work for me to do?

 May 4, 2020
 #10
avatar
0

just nee help on the question above plz

Guest May 4, 2020
 #11
avatar+171 
0

For b), all you have to do is substitute the given values into the equation.

\(u = 3 m/s \\ a = 1.5 m/s^2 \\ t = 7 s\)

 

Thus we get:

\(v=3 m/s + 1.5m/s^2 \cdot 7 s \\ v=\boxed{13.5 m/s}\)

 May 4, 2020

25 Online Users

avatar
avatar
avatar