16,900,000 in scientific notation is 16.9 times 10^7.

When you move the decimal point to the 1, it goes 7 spaces to the left, so the exponent will be a positive 7.

6 0

3 years ago

Stephanie had a total of 80 pieces of $ 2 and $ 10 notes. After spending 2/5 of her $ 2 notes and 8 pieces of her $ 10 notes, sh

Ghella [55]

Answer:

$440

Step-by-step explanation:

notes $2 - n

notes $10 - m

n + m = 80 ----------> m = 80 - n

1 - 2/5 = 3/5

$\frac{3}{5} * n = m - 8$

$\frac{3}{5} * n = 80 - n - 8 \\\\\frac{3}{5} * n + n = 72\\\\\frac{8}{5} * n = 72\\n = 45 \\m = 35\\$

45 * $2 + 35 * $10 = 90 + 350 = $440

3 0

3 years ago

What is : (49^x)(7^x^2)=2401^2

ludmilkaskok [199]

$(49^x)(7 ^{x^2})=2401^2 \\ \\( (7^2)^x)(7 ^{x^2})= (7^4) ^2 \\ \\ 7 ^{2x}\cdot 7^{x^2}=7^{8} \\ \\ 7 ^{2x+x^2} =7^{8} \\ \\2x+x^2 =8$

$x^2-2x-8 = 0\\ \\ a=1, \ b=-2, \ c=-8 \\ \\\Delta =b^2-4ac = (-2)^2 -4\cdot1\cdot (-8) = 4 +32 =36 \\ \\x_{1}=\frac{-b-\sqrt{\Delta} }{2a}=\frac{2-\sqrt{36}}{2 }=\frac{ 2-6}{2}=\frac{-4}{2}=-2 \\ \\x_{2}=\frac{-b+\sqrt{\Delta} }{2a}=\frac{2+\sqrt{36}}{2 }=\frac{ 2+6}{2}=\frac{8}{2}= 4 \\ \\Answer: \ x=-2 \ \ or \ \ x=4$

7 0

3 years ago

Read 2 more answers

What is an equation of the line that passes through the points (4,-6) and (8,-4)

qaws [65]

Answer:

$y = \frac{1}{2} x - 8$

Step-by-step explanation:

The equation of a line is usually written in the form of y=mx+c, where m is the gradient (also known as slope) and c is the y-intercept (the point through which the line cuts through the y-axis).

$\boxed{gradient = \frac{y1 - y2}{x1 - x2} }$

Using the gradient formula above,

$m = \frac{ -4 - ( - 6)}{8 - 4} \\ m = \frac{ - 4 + 6}{4} \\ m = \frac{2}{4} \\ m = \frac{1}{2}$

Substitute the value of m into the equation:

y= ½x +c

To find the value of c, substitute a pair of coordinates.

When x=4, y= -6,

-6= ½(4) +c

-6= 2 +c

c= -6 -2 (-2 on both sides)

c= -8 (simplify)

Thus, the equation of the line is y= ½x -8.

4 0

3 years ago

CIRCLE10 inrodius =?diameter = ?​

CIRCLE10 inrodius =?diameter = ?