4 years ago

Solve -3x2 + 30x - 90 = 0.

1 answer:

6 0

$-3x^{2}+30x-90=0 \\ \\ x^{2}-10x+30=0 \\ \\ \Delta=(-10)^{2}-4*1*30=100-20=-20 \\ \\ \sqrt{\Delta}= \sqrt{-20}=i \sqrt{20} =2i \sqrt{5} \\ \\ x_{1}= \frac{10-2i \sqrt{5} }{2} = 5-i \sqrt{5} \\ \\ x_{2}= \frac{10+2i \sqrt{5} }{2} = 5+i \sqrt{5}$

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Bond [772]

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3 years ago

A rectangular cooler made of MycoFoam is 13 inches wide, 7 inches tall, and 7 inches long. what is its surface area?

yarga [219]

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3 years ago

What is the value of x?

butalik [34]

Answer:

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Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

Is there a dilation that maps shape III onto shape II? If so, what is the scale factor and is it an enlargement or a reduction?

Mama L [17]

Answer:

Step-by-step explanation:

Vertex of Shape I : (1,1) (2,1) (2,2) (1,2) ---- (x,y)

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Vertex of Shape III : (2,2) (4,2) (4,4) (2,4) --- (x'',y'') -> (x' , y') : (x''*1.5 , y''*1.5)

Shape I dilate on to Shape II: Enlargement with scale factor of 3

dilation the Maps shape lll onto shape ll : Enlargement with scale factor of 1.5

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3 years ago

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RideAnS [48]

Answer:

total surface area = area of the two equilateral triangles + area of the 3 rectangles,

= 2(√3/4 a²) + 3( l x b )

= 2[√3/4 (3)²] + 3( 5 x 3 )

= 2 x 3.9 + 45

= 7.8 + 45

= 52.8 m²

6 0

3 years ago