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2 years ago

molly is 4 years younger than Heidi. In 3 years, Heidi will be twice as old as Molly. How old are they now

Mathematics

1 answer:

ASHA 777 [7]2 years ago

8 0

Answer:

Molly would be 1 years old.

Step-by-step explanation:

"In three years..."

(m+3) will be Molly's age then.

(h+3) will be Heidi's age then.

(h+3) = 2(m+3) :: given.

Subsitute what we know about m, which is it equal h-4.

(h+3) = 2(m+3)

(h+3) = 2m + 6

substitute m=h-4

(h+3) = 2(h-4) +6

h +3 = 2(h -4) +6

h +3 = 2h -8 +6

h +3 = 2h -2

h = 2h -8 +3

-h = -5

h = 5

Heidi is 5 years old now.

m = h-4

m = 5-4

m = 1

Molly is 1 years old now.

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Find an equation for the nth term of the arithmetic sequence. -3, -5, -7, -9, ...

tankabanditka [31]

Answer:

a(n) = -3 - 2(n-1)

Step-by-step explanation:

The most general formula for the nth term of an arithmetic sequence (such as this sequence is) is

a(n) = a(1) + c(n-1), where c is the common difference.

Here a(1) = -3 and c = -2.

Thus,

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3 years ago

The sycamore grove contains 30 sycamo

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Answer:

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Step-by-step explanation:

Let the total number of trees be x.

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So,75%of x=30

or,(75/100)*x=30

or,x=(30*100)/75

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3 years ago

F(x) = x2 – 2x - 8

maw [93]

Answer:

The y-intercept is the point (0,-8)

see the attached figure

Step-by-step explanation:

we have

$f(x)=x^{2}-2x-8$

we know that

The y-intercept is the value of the function f(x) when the value of x is equal to zero

For x=0

$f(x)=0^{2}-2(0)-8\\f(x)=-8$

therefore

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see the attached figure to better understand the problem

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3 years ago

Through (-4,6) and parallel to y=-3x+4

liraira [26]

Y=mx+b
parallel lines will have the same slope.

using the points (-4,6) and the slope for the parallel line -3 we can find b (the y intercept) for the line.

6 = (-3)(-4) + b
6 = 12 + b
-12 + 6 = -12 + 12 +b
-6 = b
so the line that runs through points (-4,6) and parallel to y= -3x+4 is:
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3 years ago

I need help asap. Evaluate Expressions

Anit [1.1K]

Answer:

p-r/6=-6-(-6)/6=-6+1=-5

2:

p-(m-n)= -1-(-4-4)=-1-(-8)=-1+8=7

(z+y)/2)3=(-5-4)/3=-9/3=-3

4:

m/6-n=6/6-6=1-6=-5

k³-h=3³-(-2)=27+2=29

p-(p-(m-3))=5-(5-(4-3))=5-(5-1)=5-4=1

(k)(k-j)+3=(5)(5-5)+3=5*0+3=3

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9;

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10:

y+z-(y-x)=5+4-(5-2)=9-3=6

Some basic rules:

+. +. +=+

+. * +=+

+. ÷ +=+

+. - +=+

and

+. +. -=add and put sigh of greater one.

-. * +=-sigh

-÷-=+sigh

- - -=add and put - sigh

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3 years ago

Read 2 more answers