Hi:) I need help with part 9(ii) ? Thanks :)!

see explanation

Step-by-step explanation:

Given

2BD = 7BT , then

2(d - b ) = 7(t - b) ← distribute both sides

2d - 2b = 7t - 7b ( add 7b to both sides )

2d + 5b = 7t, thus

2 + 5 = 7t

+ = 7t

= 7t , thus

t = =

Hence T = (3, 5 )

Please see the attached pictures for the full solution.

We reject x= -3 since x has to be between x=0 and x=10.5 since T lies on line BD.

We reject y= 1 since the y value has to be between 3 and 10 for T to lie on line BD.

Useful formula:

gradient=(y1-y2)/(x1-x2)

Further explanation:

1st picture, from line 12 to 13: cross multiply

line 14: expand

line 15: bring 9 over (or +9 on both sides)

line 16: ÷3 throughout

last picture: we have to show '(reject)' because whenever we introduce a square root, there must be a '±' sign.

answer: 1inch=7days  

12inch=12*7=84days

step-by-step explanation:

answer: solve 5\cdot 2^x=2405⋅2  

x

=2405, dot, 2, start superscript, x, end superscript, equals, 240.

solution

to solve for xxx, we must first isolate the exponential part. to do this, divide both sides by 555 as shown below. we do not multiply the 555 and the 222 as this goes against the order of operations!

\begin{aligned} 5\cdot 2^x& =240 2^x& =48 \\ \end{aligned}  

5⋅2  

x

2  

x

​    

=240

=48

​

step-by-step explanation: