Answer:
.
Step-by-step explanation:
Answer:
She will have 142 watermelons
Step-by-step explanation:
First let's put our ratio
10 : 71
Since our lemons are now 20 instead of 10 we will divide 20 by 10 to see how many time we multiplied it by.
which equals 2
To find our water melon we will multiply it by 2
which equals 142
She will have 142 watermelons
Answer:
4.5
Step-by-step explanation:
15% of 30 is 4.5
Answer:
tan²x + 1 = sec²x is identity
Step-by-step explanation:
* Lets explain how to find this identity
∵ sin²x + cos²x = 1 ⇒ identity
- Divide both sides by cos²x
∵ sin x ÷ cos x = tan x
∴ sin²x ÷ cos²x = tan²x
- Lets find the second term
∵ cos²x ÷ cos²x = 1
- Remember that the inverse of cos x is sec x
∵ sec x = 1/cos x
∴ sec²x = 1/cos²x
- Lets write the equation
∴ tan²x + 1 = 1/cos²x
∵ 1/cos²x = sec²x
∴ than²x + 1 = sec²x
- So we use the first identity sin²x + cos²x = 1 to prove that
tan²x + 1 = sec²x
∴ tan²x + 1 = sec²x is identity
