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3 years ago

Help me to do this please

Mathematics

1 answer:

Tanzania [10]3 years ago

7 0

If x represents the mass of 1 ball in kg, then the balance shows ...

... 6x = x + 9 kg

... 5x = 9 kg

Then 6x is ...

... (6/5)·5x = (6/5)·9 kg = 10.8 kg

0.8 kg = 0.8·1000 g = 800 g

so 10.8 kg is ...

... D. 10 kg 800 g

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F is between E and G, EF=2x-2, EG=6x+10, and FG=6x. Find x.

BartSMP [9]

Answer:

x = 6

Step-by-step explanation:

Given that F is between E and G , then

EF + FG = EG , substitute values

2x - 2 + 6x = 6x + 10 , that is

8x - 2 = 6x + 10 ( subtract 6x from both sides )

2x - 2 = 10 ( add 2 to both sides )

2x = 12 ( divide both sides by 2 )

x = 6

4 0

3 years ago

a boat takes 8 hours to go 6 miles upstream and come back to the starting point. if the speed of the boat is 4 miles per hour in

Romashka-Z-Leto [24]

Consider this option:
1. if to re-write the condition, it is given: total time t=8 hours; upstream=downstream=6 miles; V_boat=4 m/h., V_current=V=?
2. note, that total time=time_upstream+time_downstream, where time_upstream=6miles/(V_boat-V) and time_downstream=6miles/(V_boat+V). Using this it is possible to make up and solve the following equation:
$\frac{6}{4+V} + \frac{6}{4-V} =8; \ =\ \textgreater \ \ \frac{V^2-10}{16-V^2}=0; \ =\ \textgreater \ \ V=\sqrt{10} \ \frac{miles}{hour}$

answer: √10

P.S. the roots of the equation are √10 and (-√10), only positive values is needed for V.

7 0

3 years ago

A bank account yields 7 percent interest, compounded annually. If you deposit $1,000 in the account, what will the account balan

lianna [129]

Hi there
The formula is
A=p (1+r)^t
A future value?
P present value 1000
R interest rate 0.07
T time 5 years
So
A=1,000×(1+0.07)^(5)
A=1,402.55

It's a

Hope it helps

7 0

3 years ago

4y+2y+x+2x please help

DochEvi [55]

Answer:

Solution

Step-by-step explanation:

This is the best of what I got.

8 0

3 years ago

13 POINTS- please help me

allsm [11]

Answer:

See explanation

Step-by-step explanation:

16. Two parallel lines are cut by transversal. Angles with measures $(6x+20)^{\circ}$ and $(x+100)^{\circ}$ are alternate exterior angles. By alternate exterior angles, the measures of alternate exterior angles are the same:

$6x+20=x+100\\ \\6x-x=100-20\\ \\5x=80\\ \\x=16$

Then

$(6x+20)^{\circ}=(6\cdot 16+20)^{\circ}=116^{\circ}\\ \\(x+100)^{\circ}=(16+100)^{\circ}=116^{\circ}$

17. Two parallel lines are cut by transversal. Angles with measures $(2x+12)^{\circ}$ and $(3x-22)^{\circ}$ are alternate interior angles. By alternate interior angles, the measures of alternate interior angles are the same:

$2x+12=3x-22\\ \\2x-3x=-22-12\\ \\-x=-34\\ \\x=34$

Then

$(2x+12)^{\circ}=(2\cdot 34+12)^{\circ}=80^{\circ}\\ \\(3x-22)^{\circ}=(3\cdot 34-22)^{\circ}=80^{\circ}$

18. Two parallel lines are cut by transversal. Angles with measures $(6x-7)^{\circ}$ and $(5x+10)^{\circ}$ are alternate exterior angles. By alternate interior angles, the measures of alternate exterior angles are the same:

$6x-7=5x+10\\ \\6x-5x=10+7\\ \\x=17$

Then

$(6x-7)^{\circ}=(6\cdot 17-7)^{\circ}=95^{\circ}\\ \\(5x+10)^{\circ}=(5\cdot 17+10)^{\circ}=95^{\circ}$

19. The diagram shows two complementary angles with measures $2x^{\circ}$ and $56^{\circ}$ . The measures of complementary angles add up to $90^{\circ},$ then

$2x+56=90\\ \\2x=90-56\\ \\2x=34\\ \\x=17$

Hence,

$2x^{\circ}=2\cdot 17^{\circ}=34^{\circ}$

Check:

$34^{\circ}+56^{\circ}=90^{\circ}$

20. Angles $\angle 1$ and $\angle 2$ are vertical angles. By vertical angles theorem, vertical angles are congruent, so

$m\angle 1=m\angle 2\\ \\5x+7=3x+15\\ \\5x-3x=15-7\\ \\2x=8\\ \\x=4$

Hence,

$m\angle 1=(5x+7)^{\circ}=(5\cdot 4+7)^{\circ}=27^{\circ}\\ \\m\angle 2=(3x+15)^{\circ}=(3\cdot 4+15)^{\circ}=27^{\circ}$

21. $\angle 5$ and $\angle 8$ are supplementary. The measures of supplementary angles add up to $180^{\circ},$ so

$m\angle 5+m\angle 8=180^{\circ}\\ \\3x-40+7x-120=180\\ \\10x-160=180\\ \\10x=180+160\\ \\10x=340\\ \\x=34$

Therefore,

$m\angle 5=(3x-40)^{\circ}=(3\cdot 34-40)^{\circ}=62^{\circ}\\ \\m\angle 8=(7x-120)^{\circ}=(7\cdot 34-120)^{\circ}=118^{\circ}\\ \\62^{\circ}+118^{\circ}=180^{\circ}$

7 0

3 years ago