Answer: 25x² - 64
<u>Step-by-step explanation:</u>
(5x + 8)(5x - 8)
= 5x(5x - 8) + 8(5x - 8)
= 25x² - 40x + 40x - 64
= 25x² + 0x - 64
= 
NOTE: descending powers means the biggest exponent goes first, then the next biggest exponent, etc.
For example: x⁴ then x³ then x² then x then the number (which is actually x⁰)
4x+5 = 8x - 11
4x - 8x = -11 - 5
-4x = -16
x = 4
4x+5 = 4(4) +5 = 21
8x - 11 = 8(4) - 11 = 21
<RST = 21 + 21 = 42
answer
<RST = 42 degrees
Answer:
3
Explanation:
4 is half of 8 on the right side, so that means X has to be half of 6, so it’s 3. Also, it couldn’t be 2 because it is too big, and it can’t be 4 because it isn’t the same length as the other 4, so it’s 3
Answer:
the container is 1/4 full at 9:58 AM
Step-by-step explanation:
since the volume doubles every minute , the formula for calculating the volume V at any time t is
V(t)=V₀*2^-t , where t is in minutes back from 10 AM and V₀= container volume
thus for t=1 min (9:59 AM) the volume is V₁=V₀/2 (half of the initial one) , for t=2 (9:58 AM) is V₂=V₁/2=V₀/4 ...
therefore when the container is 1/4 full the volume is V=V₀/4 , thus replacing in the equation we obtain
V=V₀*2^-t
V₀/4 = V₀*2^-t
1/4 = 2^-t
appling logarithms
ln (1/4) = -t* ln 2
t = - ln (1/4)/ln 2 = ln 4 /ln 2 = 2*ln 2 / ln 2 = 2
thus t=2 min before 10 AM → 9:58 AM
therefore the container is 1/4 full at 9:58 AM
