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3 years ago

Help me please asap n\like now

Mathematics

2 answers:

Svetllana [295]3 years ago

6 0

46 square inches should be your answer

kompoz [17]3 years ago

4 0

Answer:

46 square inches

Step-by-step explanation:

You might be interested in

In evaluating a double integral over a region D, a sum of iterated integrals was obtained as follows:

BabaBlast [244]

Answer

$a=0$ , $b=2$

$g_1(x)=\frac{5x}{2}$ , $g_2(x)=7-x$

Step-by-step explanation:

Given that

$\int \int Df(x,y)dA=\int_0 ^5\int _0 ^ {\frac {2y}{5}} f(x,y)dxdy+\int_5^7\int_0^{7-y} f(x,y)dxdy\; \cdots (i)$

For the term $\int_0 ^5\int _0 ^ {\frac {2y}{5}} f(x,y)dxdy$ .

Limits for $x$ is from $x=0$ to $x=\frac {2y}{5}$ and for $y$ is from $y=0$ to $y=5$ and the region $D$ , for this double integration is the shaded region as shown in graph 1.

Now, reverse the order of integration, first integrate with respect to $y$ then with respect to $x$ . So, the limits of $y$ become from $y=\frac{5x}{2}$ to $y=5$ and limits of $x$ become from $x=0$ to $x=2$ as shown in graph 2.

So, on reversing the order of integration, this double integration can be written as

$\int_0 ^5\int _0 ^ {\frac {2y}{5}} f(x,y)dxdy=\int_0 ^2\int _ {\frac {5x}{2}}^5 f(x,y)dydx\; \cdots (ii)$

Similarly, for the other term $\int_5 ^7\int _0 ^ {7-y} f(x,y)dxdy$ .

Limits for $x$ is from $x=0$ to $x=7-y$ and limits for $y$ is from $y=5$ to $y=7$ and the region $D$ , for this double integration is the shaded region as shown in graph 3.

Now, reverse the order of integration, first integrate with respect to $y$ then with respect to $x$ . So, the limits of $y$ become from $y=5$ to $y=7-x$ and limits of $x$ become from $x=0$ to $x=2$ as shown in graph 4.

So, on reversing the order of integration, this double integration can be written as

$\int_5 ^7\int _0 ^ {7-y} f(x,y)dxdy=\int_0 ^2\int _5 ^ {7-x} f(x,y)dydx\;\cdots (iii)$

Hence, from equations $(i)$ , $(ii)$ and $(iii)$ , on reversing the order of integration, the required expression is

$\int \int Df(x,y)dA=\int_0 ^2\int _ {\frac {5x}{2}}^5 f(x,y)dydx+\int_0 ^2\int _5 ^ {7-x} f(x,y)dydx$

$\Rightarrow \int \int Df(x,y)dA=\int_0 ^2\left(\int _ {\frac {5x}{2}}^5 f(x,y)+\int _5 ^ {7-x} f(x,y)\right)dydx$

$\Rightarrow \int \int Df(x,y)dA=\int_0 ^2\int _ {\frac {5x}{2}}^{7-x} f(x,y)dydx\; \cdots (iv)$

Now, compare the RHS of the equation $(iv)$ with

$\int_a^b\int_{g_1(x)}^{g_2(x)} f(x,y)dydx$

We have,

$a=0, b=2, g_1(x)=\frac{5x}{2}$ and $g_2(x)=7-x$ .

3 0

3 years ago

Which is a better by 3 lb of pears for $3.87 or 5 lb of pears for $6.65

Shtirlitz [24]

Since 3lb pears is $3.87 lets say that every 1lb of pears costs $1.30.
say if you were to buy 2lb on-top of the 3lb it would cost $2.60 extra, causing the total price to be around $6.50 (rounded up)

so since 5lb is $6.65, i believe that the 3lb of pears is the better buy.

7 0

3 years ago

Read 2 more answers

3/4 n + 7 = 28 - nn =

Readme [11.4K]

if i'm correct n= 1 if you need a explanation let me know

3 0

3 years ago

Make X the subject: 8x+9y=gx+5z

alexira [117]

Answer:

x = $\frac{5z-9y}{8-g}$

Step-by-step explanation:

Given

8x + 9y = gx + 5z ( subtract gx from both sides )

8x - gx + 9y = 5z ( subtract 9y from both sides )

8x - gx = 5z - 9y ( factor out x on the left side )

x(8 - g) = 5z - 9y ← divide both sides by (8 - g)

x = $\frac{5z-9y}{8-g}$

8 0

3 years ago

Dana drives her car 12 miles in 30 minutes...<br> Find the number of miles she drives in 1 hour

Mashutka [201]

Answer:

Step-by-step explanation:

12 miles is done in 30 minutes, so if you multiply 12 x 2 (because 30+30=60 and 60 minutes = an hour) you would get the answer of 24.

3 0

3 years ago