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In the triangle ABC, ab = AC, the acute angle obtained by the intersection of the vertical line of AB and the line where AC is located is 40 degrees, then what is the degree of the base angle B
Two cases
When ∠ A is an acute angle, the intersection of the vertical bisector of AB and AC is on AC
At this time ∠ BAC = 50 °
∴∠B=65°
When ∠ A is an obtuse angle, the intersection of the vertical bisector of AB and AC is on the extension line of ca
At this time ∠ BAC = 130 °
∴∠B=25°
In △ ABC, ab = AC, and the acute angle obtained by the intersection of the vertical bisector of AB and the line where AC is located is 50 °, then ∠ B is equal to______ ．
According to ∠ a as acute angle and obtuse angle in △ ABC, it can be divided into two cases: ① when ∠ A is acute angle, the acute angle obtained by the intersection of the vertical bisector of ∵ AB and the straight line of AC is 50 °, and ∵ a = 40 °, and ∵ B = 180 − A2 = 180 − 40 ° 2 = 70 °. ② when ∵ A is obtuse angle, the vertical bisector of ∵ AB and the straight line of AC are
It is known that in the triangle ABC, ab = AC, the acute angle obtained by the intersection of the vertical bisector of AB and the line where AC is located is 40 degrees, and the degree of the base angle B is calculated
Please attach a picture
If the finger presses the pencil point with 1n force, the pressure of the pencil on the horizontal table is___ N (the gravity on the pencil is negligible)
As shown in the figure, the finger presses the pencil tip with 1n force, and the pressure of the pencil on the horizontal desktop is________ N (the gravity of the pencil is neglected), the contact area between the finger and the pencil tip is 0.5mm2, the contact area between the end of the pen and the desktop is 0.4cm2, and the pressure on the finger is 0.5mm2_________ PA, what is the pressure on the table__________ Pa.
As shown in the figure, the finger presses the pencil tip with 1n force, and the pressure of the pencil on the horizontal desktop is___ 1___ N (the gravity of the pencil is neglected), the contact area between the finger and the pencil tip is 0.5mm2, the contact area between the end of the pen and the desktop is 0.4cm2, and the pressure on the finger is 0.5mm2____ 2000 000_____ PA, what is the pressure on the table____ ...
A kind of cylindrical pencil with a diameter of 0.8 cm. The paint area of each pencil is known to be 45.216 square cm. Find the length of the pencil
From the bottom diameter of 0.8 cm, the perimeter of the bottom is 2.512 square cm (2x3.14x0.8 / 2)
The pencil length is equal to the paint area divided by the perimeter of the bottom surface, which is 18 cm (45.216 / 2.512)
A kind of wooden pencil is 20 cm long and 0.8 cm in diameter at the bottom. A pen factory produces 500000 pieces of this pencil every year, which costs at least wood
How many cubic meters?
The volume of a pencil = 3.14 × (0.8 △ 2) &# 178; × 20 = 10.048 cubic centimeter
500000 pieces of wood consumption = 10.048 × 500000 = 5024000 cm3 = 5.024 M3
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Xiaoqiang bought a pen and a pencil in the stationery shop. It costs 3 yuan and 60 cents. For one pen, you can buy three pencils. How much is a pencil
The pencil is 90 cents and the pen is 2.7 yuan
If there are 210 pencils on the V-shaped shelf, how many pencils are there on the top?
Let V-frame have n layers, then the top layer has n pencils, 12n (n + 1) = 210, so n (n + 1) = 420, because 420 = 21 × 20, so n = 20, that is, V-frame has n layers, and the top layer has 20 pencils
This is a V-shaped shelf for stacking pencils. If there are 60 pencils on the top layer, how many pencils are there?
If there are 210 pencils on the V-frame, how many pencils are on the top?
This is a problem related to sequence, which can be regarded as arithmetic sequence, one at the lowest level, two at the second level, three at the third level
According to the summation formula of arithmetic sequence
210=（1+n）n/2
n=20
a20=a1+19=1+19=20
If there are 210 pencils on the V-shaped shelf, how many pencils are there on the top?
Let V-frame have n layers, then the top layer has n pencils, 12n (n + 1) = 210, so n (n + 1) = 420, because 420 = 21 × 20, so n = 20, that is, V-frame has n layers, and the top layer has 20 pencils
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