PLEASSSSSE HELPPPPPP This is my third post of this! I really need help

Mathematics

1 answer:

Nesterboy [21]3 years ago

6 0

Answer: x=25

solution:

we know that
The triangle external angle theorem states that: An exterior angle of a triangle is equal to the sum of the opposite interior angles

In this problem:
m∠9=m∠7+m∠8

substitute the given values:
(6x-20)°=30°+4x°

now solve for x:
6x-4x=30+20
2x=50
x=25 which is the final answer:)

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Help pls pls I really need help

Misha Larkins [42]

C is correct bc if you add 10 to x you get the value of y

5 0

2 years ago

Read 2 more answers

A tanker of capacity 200 litres has 12.05 litres of oil. how much more oil can be poured into the tanker ?

Scilla [17]

Answer:

187.95 liters.

Step-by-step explanation:

the entire capacity of the tank is 200 liter, you subtract how much oil is in there already, you will have the remaining Of the capacity that can be added.

200 - 12.05 = 187.95

3 0

3 years ago

What % of 400 = 193

saveliy_v [14]

The best way to find your answer is to divide 193 by 400 to get .4825 and to make sure if it is the answer you take 400 and multiply .4825 and it will be 193 so .4825 = 48.25%

3 0

3 years ago

A jeweler wants to make 14 grams of an alloy that is precisely 75% gold.. The jeweler has alloys that are 25% gold, 50% gold, &a

Goryan [66]

Given that the jeweler has alloys that are 25% gold, 50% gold, and 82% gold.

As he wants to make 14 grams of an alloy by adding two different alloys that is precisely 75% gold, so one alloy must have a percentage of gold more than 75%.

One alloy is 82% gold and, the second can be chosen between 25% gold, 50% gold, so there are two cases.

Case 1: 82% gold + 50% gold

Let x grams of 82% gold and y grams of 50% gold added to make x+y=14 grams of 75% gold, so

75% of 14 = 82% of x + 50% of y

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 50/100 \times y \\\\$

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 50/100 \times (14-x)$ [as x+y=14]

$\Rightarrow 75 \times 14 = 82 \times x + 50 \times (14-x) \\\\\Rightarrow 75 \times 14 = 82 \times x + 50 \times14-50\times x \\\\\Rightarrow 75 \times 14 = 32 \times x + 50 \times14 \\\\\Rightarrow 32 \times x =75 \times 14 - 50 \times14 \\\\$

$\Rightarrow x =(25 \times 14)/32=10.9375$ grams

and $y = 14-x= 14-10.9375=3.0625$ grams.

Hence, 10.9375 grams of 82% gold and 3.0625 grams of 50% gold added to make 14 grams of 75% gold.

Case 2: 82% gold + 25% gold

Let x grams of 82% gold and y grams of 25% gold added to make x+y=14 grams of 75% gold, so

75% of 14 = 82% of x + 25% of y

$\Rightarrow 75/100 \times 14 = 82/100 \times x + 25/100 \times y \\\\\Rightarrow 75/100 \times 14 = 82/100 \times x + 25/100 \times (14-x) \\\\ \Rightarrow 75 \times 14 = 82 \times x + 25 \times (14-x) \\\\\Rightarrow 75 \times 14 = 82 \times x + 25 \times14-25\times x \\\\\Rightarrow 75 \times 14 = 57 \times x + 25 \times14 \\\\\Rightarrow 57 \times x =75 \times 14 - 25 \times14 \\\\$