The solution equation is 4x-7 = 5 What is x equal to

The solution equation is 4x-7 = 5 What is x equal to

4X-7=5
4X=5+7
4X=12
X=12/4
X=3
How to solve 13 * 7 + 4x = 127 equation
13*7+4x=127
91+4x=127
4x=127-91
4x=36
x=36/4
X=9
After studying for so many years, I forgot how to solve the equation: 4x of 7 + x = 22 of 49
4X of 7 + x = 22 of 49
4/7x+x=22/49
11/7x=22/49
x=22/49 * 7/11
x=2/7
Given that the value of 2x & # 178; + 3x is 82, find the value of - 4x & # 178; - 6x + 9,
-4x²-6x+9
=-2(x²+3x)+9
=-2x82+9
=-164+9
=-155
∵ 2x & # 178; + 3x is 82
∴ 2x²+3x=82
∴-4x²-6x+9=-2﹙2x²+3x﹚+9=-2×82+9=-155
-4x^2-6x+9=-2(2x^2+3x)+9=-2*82+9=-155
It is proved that the circle whose diameter is the focus chord of the parabola must be tangent to the parabola
Draw a picture by yourself
Proof: AB is a string of parabola y ^ 2 = 2px (P > 0) passing through focus F
Let m be the middle point of AB, the perpendicular line passing through a, B and m respectively, and the perpendicular feet are A1, B1 and M1 respectively
According to the definition of parabola, AF = Aa1, BF = BB1,
So AB = AF + BF = Aa1 + BB1
MM1 is the median line of aa1bb1,
So AB = Aa1 + BB1 = 2mm1
Therefore, AM1B = 90 degree
And MM1 is perpendicular to the guide line,
Then the circle with diameter AB must be tangent to the parabola
(1) 3% x + 2% 1 (3% 2X-4) = 2 (2) 0.02% 0.3x-1-0.5% 4x-8 = 1
(1) X of 3 + 1 of 2 (2X-4 of 3) = 2
1/3x+1/3x-2=2
2/3x=4
X=6
(2) 0.02 (0.3x-1) - 0.5 (4x-8) = 1
50（0.3x-1）-2（4x-8）=1
15x-50-8x+16=1
7x=35
X=5
Simple math problems in Senior Two
How to calculate the distance from m (2,5) to the straight line L: x = 25 / 4?
Because l line is perpendicular to X axis, the distance between m point and L line is the distance of X axis coordinate, that is 25 / 4-2 = 17 / 4
√[(x-2)²+5²]=6.56
When y = 0, take 25 | 4 minus 2
Finding the unknown: 8 (3x-6) = 6 (4x-7) - 3 (2x + 1)
8(3x-6)=6(4x-7)-3(2x+1)
24x-48=24x-42-6x-3
24x-24x+6x=-42-3+48
6x=3
x=0.5
It is known that the minimum value of even function f (x) defined on real number set R is 3, and when x ≥ 0, f (x) = 3E ^ x + a (a is a constant), the analytic expression of function f (x) is obtained
Even function: F (x) = f (- x)
x> When f = 0, f (x) = 3E ^ x + a
E ^ X / monotone increasing
When x = 0, the minimum value is 3
f(0)=3+a=3
a=0;
f(x)=3e^x;
X
(8-4x)/(x^2+3x)+(2x-3)/(x+3)=2
Solving fractional equation
(8-4x)/(x^2+3x)+(2x-3)/(x+3)=2
(8-4x)/x(x+3)+(2x-3)/(x+3)=2
Multiply both sides by X (x + 3)
8-4x+2x^2-3x=2x^2+6x
-13x=-8
x=8/13
Equal to 8 / 13... Ask: seeking process