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When the side length of a square increases by 3cm, its area increases by 39cm2. The side length of the square is () A. 5cmB. 6cmC. 8cmD. 10cm
Let the original side length of the square be x, then x2 + 39 = (x + 3) 2, the solution is x = 5, so a
After adding 3cm to the two adjacent sides of a square, we get a new square. The area of the new square is 39 square centimeters larger than that of the original square. What's the area of the original square?
Let the side length of the original square be x cm. According to the meaning of the question, we can get: 3x + 3x + 3 × 3 = 39 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 6x + 9 = 39 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 6x = 30 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 5 the area of the original square: 5 × 5 = 25 (square centimeter) a: the area of the original square is 25 square centimeter
If the side length of a square is increased by 3 cm, the area will be increased by 39 square cm?
The original side length
（39-3x3）÷（3+3）
=30÷6
=5 cm
Original area
5x5 = 25 square centimeters
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After adding 3cm to the two adjacent sides of a square, we get a new square. The area of the new square is 39 square centimeters larger than that of the original square. What's the area of the original square?
Let the side length of the original square be x cm. According to the meaning of the title, we can get: 3x + 3x + 3 × 3 = 39 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 6x + 9 = 39 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 6x = 30 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 5 the original square
Right triangle, know the value of two straight lines, want to calculate the length of the diagonal, how to calculate ah, what is the formula? Urgent '!
Pythagorean theorem
The right angle is a and B, and the hypotenuse is C
The formula A ^ 2 + B ^ 2 = C ^ 2 ^ 2 means square
Right triangle bottom length 3, oblique length 9, find the other side length formula
The square of nine minus the square of three is below the root sign
The length of the right triangle is 5 and 12 respectively. How much is the height of the hypotenuse
From Pythagorean theorem
Root 5 square + root 12 square is 13
If both sides of a right triangle are 5 and 12 long, the height of the hypotenuse is
Do it by area method
The length of the hypotenuse is: 5 square + 12 square root = 13
(1 / 2) * 5 * 12 = (1 / 2) * 13 * height on hypotenuse
30 = (13 / 2) * height on hypotenuse
Height on hypotenuse = 60 / 13
What is the height of the hypotenuse of a right triangle with 14 right angles and 12 hypotenuses
Let the right angle side be a, B and the hypotenuse be C, then a + B = 14, a ^ 2 + B ^ 2 = 144, so 2Ab = 14 ^ 2-12 ^ 2 = 52, that is, ab = 26. If there is an area formula, c * H = AB, that is, 12h = 26, that is, H = 13 / 6
The sum of the two right angles of a right triangle is 14 cm, and the area is 12 square cm. Find the length of the two right angles
Let one side be x cm long and the other 14-x cm long
X*(14-X)=12×2
x²-14x+24=0
(x-12)(x-2)=0
x1=12 x2=2
The length of the two right angles is 12 cm and 2 cm respectively
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