class 8 maths ncert try these page number 173 and 175
Answers
Answer:
Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes, and 4 seconds with respect to other, distant, stars (see below). Earth's rotation is slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth's rotation.Fluoride is the most crucial ingredient in toothpaste. As long as the toothpaste contains fluoride, the brand or type (paste, gel, or powder) generally does not matter. All fluoride toothpastes work effectively to fight plaque and cavities, and clean and polish tooth enamel.Diwali is a Hindu festival that is known as the festival of lights. This festival usually lasts for five days and is celebrated during the Hindu month of Kartika. The festival symbolizes the spiritual “victory of light over darkness.” In India, Diwali is also known as Dipawali.Slope of the given line = slope of AB=
−2−3
4−7
=
5
3
. Thus, m=
5
3
∴ required equation is
x−4
y+5
=
5
3
⇔3x−5y−37=0How many straight lines can be formed by joining any two of the eight points when no three of them are collinear?
Each pair of points determines a unique line. So (82)=28(82)=28 is the answer to your question.2 points are required for a line , so from 20 points total no. of lines are 20C2.
but 4 points are linear so lines formed from these 4 points would be identical.
so substract 4C2 from total.
hence answer is 20C2 - 4C2 +1 .
20*19/2 - 4*3/2 +1
190 - 6 +1
185
