How do you simplify 2√5+3√5-√5

1 answer:

7 0

We can simplify 2√5+3√5-√5 because they all have the same radical, √5. Now that we know this, we can imagine that there are no radicals, and that we are just adding numbers. This results in our expression being 2 + 3 - 1. This gives an answer of 4. Finally, we add the √5 to the 4 to get 4√5.

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And here is the other one.

LUCKY_DIMON [66]

Since BD bisects angle ABC, that means angle ABD and angle CBD are equal to each other. With that set up the equation to solve for x like this:

-4x+33 = 2x+81
-2x -2x
————————
-6x +33 = 81
-33 -33
————————
-6x = 48
————- (divide by -6)
-6

x = -8

Now substitute that to ABD
-4(-8) +33
32 +33
=65

here’s CBD
2(-8) + 81
-16 + 81
=65

Finally angle ABC will be double the amount of ABD or CBD so 65 times 2 is 130.

ANSWERS: (angles)
ABD and CBD: 65
ABC: 130

3 0

3 years ago

How many times does the graph of 4x = 32 - x2 cross the x-axis?

garik1379 [7]

Answer:

The graph crosses the x-axis 2 times

The solutions are x = -8 & x = 4

Step-by-step explanation:

Qaudratics are in the form $ax^2 + bx+ c$

Where a, b, c are constants

Now, let's arrange this equation in this form:

$4x=32-x^2\\x^2+4x-32=0$

Where

a = 1

b = 4

c = -32

We need to know the discriminant to know nature of roots. The discriminant is:

$D=b^2-4ac$

D = 0 , we have 2 similar root and there is 2 solutions and that touches the x-axis
D > 0, we have 2 distinct roots/solutions and both cut the x-axis
D < 0, we have imaginary roots and it never cuts the x-axis

Let's find value of Discriminant:

$D=b^2-4ac\\D=(4)^2 -4(1)(-32)\\D=144$