This one is harder,all i know right now is that it will take him 3 days and 8 hr,but i will get back to u.
The constant rate of change is 2
(The y intercept is 20 so subtract 20 from the y and divide by 2 to get your x)
Answer:
Step-by-step explanation:
<u>The correct question is:</u> If the first, second and last term of an AP are a,b and 2a respectively, then show that the sum of all terms of an AP is 3ab/2(b-a).
Firstly, as we know that the nth term of an A.P. is given by the following formula;
, where a = first term of AP, d = common difference, n = number of terms in an AP and = last term
Since it is given that the first, second and last term of an AP are a,b and 2a respectively, that means;
first term = a
d = second term - first term = b - a
= 2a
So,
------------- [equation 1]
Now, the formula for the sum to n terms of an AP when the last term is given to us is;
{using equation 1}
Hence proved.
Answer:
35
Step-by-step explanation:
Here we see 5 black keys for every 7 white keys.
So the ratio is 5:7
If we need 49 white keys, find the amount we scale the original ratio by:
49/7 = 7
So we are scaling by a factor of 7.
The number of black keys would be 5 * the scale of 7. = 35
So there should be 35 black keys.