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3 years ago

Can someone answer this please

Mathematics

2 answers:

Nana76 [90]3 years ago

6 0

Area is trapezium =
A=1/2h(a+b)

84=1/2(6)(7+b)

84=3(7+b)

84=21+3b

3b=84-21

B=63/3

B= 21 cm

I’m sorry if my answer turned out to be wrong but I tried my best so best of luck !!

LiRa [457]3 years ago

5 0

Answer:

x = 14

Step-by-step explanation:

Please note, the word trapezium is a synonym for the word trapezoid.

This problem gives one the area of the trapezoid, a well as one of the measurements of a base and the height of the figure. One is asked to find the length of the other base. This can be done by using the formula to find the area of a trapezoid. This formula is the following,

$A=(h)(\frac{b_1+b_2}{2})$

Where (A) represents the area of a trapezoid, ( $b_1$ ) and ( $b_2$ ) represents the bases and (h) represents the height. Substitute in the given values and solve for the unknown base.

$b_1=7\\h=6\\A=84$

$A=(h)(\frac{b_1+b_2}{2})\\$

Substitute,

$84=6(\frac{7+b_2}{2})\\$

Inverse operations,

$84=6(\frac{7+b_2}{2})$

$14=\frac{7+b_2}{2}$

$28=7+b_2$

$14=b_2$

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Step-by-step explanation:

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3 years ago

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Answer:

Step-by-step explanation:

f(1) = 7

f(n) = 3f(n-1) + 3

So what you are trying to do here is find the recursive value (that's what it is called) for f(n). Computers love this sort of thing, but we humans have to do it slowly and carefully.

So let's try f(2)

That means that f(2) = 3*f(n-1) + 3

but if f(2) is used it means that you have to know f(2-1) which is just f(1) and we know that.

so f(2) = 3*f(1)+3

f(2) = 3*7 + 3

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Now do it again. We now know F(2), so we should be able to find f(3)

f(3) = 3*f(3 - 1) + 3

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