Let x to the second power + y to the second power + 2 = 3, find the value of - 3x to the second power - 3Y to the second power

Let x to the second power + y to the second power + 2 = 3, find the value of - 3x to the second power - 3Y to the second power

x^2+y^2+2=3
x^2+y^2=1
-3x^2-3y^2
=-3(x^2+y^2)
=-3*1
=-3

When x + y = 8, X-Y = 2, find the square of the algebraic formula x-xy + y
Given a & # 178; - 2b-3 = 0, find the value of the algebraic formula 2A & # 178; - 4B + 5
It is known that when x = 2, the value of the algebraic formula ax & # 178; + BX is 3, and the value of the algebraic formula (8a + 4b) &# 178; - 6a-3b + 3

When k = (), the algebraic formula X & #178; - 3kxy + 6xy-8 contains no XY term

Solution
x²-3kxy+6xy-8
=x²+(6-3k)xy-8
If there is no XY term, then 6-3k = 0
∴k=2

What is the sum of 3 ^ 2-6 (K-5 / 6) XY + 4Y ^ 2-3xy + 2012 without XY

After merging the similar terms, the coefficient of XY is - 6 (K-5 / 6) - 3, because there is no XY term, we can know that the coefficient is 00, that is - 6 (K-5 / 6) - 3 = 0, and the solution is k = 1 / 3

Solving the first order equation: 5 / 3-6x = [(- 7 / 2) x] + 1
All '/' are fractional lines

3/5--6x=[(--2/7)x]+1
3/5--6x=(-2/7)x+1
21--210x=--10x+35
--200x=14
x=--0.07

What is sin0

In the rectangular coordinate system. Sin0 is the opposite side, so it is 0

How to solve this equation

x÷5-36=54
x÷5=54+36
x÷5=90
x=90×5
x=450

Xiao Jun has read 40 pages of a story book, and the ratio of reading to the rest is 2:3. How many pages are there in this book?

40 divided by 2 = 20 pages 20x (2 + 3) = 100 pages

As shown in the figure, in the plane rectangular coordinate system, the quadrangle abod is a square with a side length of 10, and the moving point P moves at a speed of 4 unit lengths per second
Point B starts to move along b-a-d-0 - B, and moving point Q starts from point B at a speed of 1 unit length per second and moves along ray b 0. Two points start at the same time. When one point stops moving, the other point also stops moving. Let their moving time be T seconds. (1) when t = 12 seconds, find the coordinates of point P and point q? (2) when P and point Q meet, find the value of T, And write out the coordinates of point P? (3) when point P moves on broken line b-a-d, find the value of T when AP = 2BQ?

(1) According to the meaning of the question, in t second, AP = 2T, BQ = t, Op = | 6-2t |, OQ = 8 + T. there are two cases: 1. If △ poq ∽ AOB, then when OP and OA are corresponding sides, op / OA = OQ / ob, that is | 6-2t | 6 = 8 + T 8, that is | 6-2t | 6 = 8 + T 8

What is 380% X (5 / 38-1 / 30)?

380% X (5 / 38-1 / 30) = 28 / 75