Using the Sine Rule:-
20 /sin 45 = BC / sin 30
BC = 20 sin 30 / sin45
= 20 * 1/2 / 1 / sqrt2
= 20 * 1/2 * sqrt2
= 10 sqrt2 answer
Answer:
x=21
Step-by-step explanation:
Following the vertical angles, we can assume that the equation that has x and 87 are equal to each other. From then, you set them equal to each other and solve for x.
87=4x+3
84=4x subtract 3 from both sides
21=x divide by 4 to get the x alone on both sides
9514 1404 393
Answer:
(b) a[1] = -7, a[n] = a[n-1] + 3
Step-by-step explanation:
Comparing the given formula to the general form for the n-th term of an arithmetic sequence ...
an = a1 +d(n -1)
we see that the first term (a1) is -7, and the common difference (d) is +3.
The recursive version of the sequence definition is ...
a[1] = a1
a[n] = a[n-1] +d
So, the appropriate choice is ...
a[1] = -7, a[n] = a[n-1] +3
Answer:
12
Step-by-step explanation:
This question means 3/(1/4). The rule for division of fractions is invert the denominator and multiply. 3/(1/4) = 3 * 4 = 12. Another way to think of it is to imagine you have 3 pies each divided into quarters.
Answer:

Step-by-step explanation:
the 6th power of 10 would be 10^6, then you'd multiply it by 3 which would make it 10^6*3
you could then simplify it and say 10^18 (multiply the exponents [6 and 3])