How do I solve for 7y-4x=42 x=5y+9

Mathematics

1 answer:

8_murik_8 [283]3 years ago

8 0

Answer:

x=-21 y=-6

Step-by-step explanation:

7y-4(5y+9)=42

7y-20y-36=42

-13y=78

y=-6

x=5*(-6)+9

x=-30+9

x=-21

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Tbh this question confusing the **** outta me

trapecia [35]

Answer:

$8^6$

Step-by-step explanation:

Powers are defined as the number of times you multiply a number by itself. For example, 2 to the 3rd power is 2 multiplied by itself 3 times. 2 * 2 * 2 = 8. You also know that if you multiply two powers of the same base, you add the exponent, and if you raise a power to a different power, you multiply the exponents.

e.g:

$2^2\cdot2^2=2^{2+2}=2^4\\(2^2)^3=2^{2\cdot3}=2^6$

Now, we are asking to use grouping to write 2 to the power 18 as a power of 8. We know 2 to the power 8 is 2 to the power 3, so we have the following equation:

$2^{18}=(2^3)^x$

We know this is now 2 to the power 3x = 2 the power 18, and therefore x = 6, because 3 times 6 is equal to 18. Now, we can just simplify 2 to the third as 8 and we now have:

$8^6$

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2 years ago

In the Kite Club, there are a total of 23 kids. There are 7 more girls than boys. Write two equations below to represent the sit

Iteru [2.4K]

Answer:

b + b + 7 = 23

2b + 7 = 23

Step-by-step explanation:

b = girls

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3 years ago

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Three students attempt to define what it means for lines lll and mmm to be perpendicular.

Vanyuwa [196]

Please find diagram attached

Answer and explanation:

Perpendicular lines are lines that meet at 90 degrees/ right angle.

The question seems to be incomplete but I will explain what perpendicular lines are in the context of lines lll and mmm, with some assumptions about the lines.

Assume that line III is 30mm long and line mmm is 25mm long, we say that line III is perpendicular to line mmm if line III meets line mmm at 90 degrees as we see in the diagram attached.