There is an app called photo math I’m not sure if you have heard about it but it’s free. I’m not to good at math so I use it often. You should download it. You take a picture of the problem and it gives you step by step directions on how to solve each problem.
One) One millivolt is one thousandths of a volt.
Two) One megagram is one million grams.
First question:
1. Set equations equal to each other so 5x-9=2x+6
2. Put x's on one side so that 3x=15
3. Divide by 3 so that x=15
4. Substitute 15 in for x so that y=2(15)+6
5. Solve for y so that y=36
6. Thus the equations intersect at (15,36)
Second question:
1. Since for lines y=mx+b, and m=slope=3 you only need to write an equation with slope 3
2. y=3x+b, b can be any number
Answer:
the third option
Step-by-step explanation:
what does that mean ?
to "rationalize" it is to transform it into a rational number (that is a number that can be described as a/b, and is not an endless sequence of digits after the decimal point without a repeating pattern).
a square root of a not square number is irrational (not rational).
so, what this question is asking us to get rid of the square root part in the denominator (the bottom part).
for this we need to multiply to and bottom with the same expression (to keep the whole value of the quotient the same) that, when multiplied at the bottom, eliminates the square root.
what can I multiply a square root with to eliminate the square root ? the square root again - we are squaring the square root.
so, what works for 9 - sqrt(14) as factor ?
we cannot just square this as
(9- sqrt(14))² = 81 -2sqrt(14) + 14
we still have the square root included.
but remember the little trick :
(a+b)(a-b) = a² - b²
without any mixed elements.
so, we need to multiply (9-sqrt(14)) by (9+sqrt(14)) to get
81-14 = 67 which is a rational number.
therefore, the third answer option is correct.
Answer:
13.4
Step-by-step explanation:
AB =2DC
So, DC=AB/2
Now, AB/AC=DE/DC
AB/28=13/(AB/2)
AB²=13×28×2
AB=√728
AB=26.98
now, DC=AB/2
=13.4
