When x = 3, the value of the algebraic formula ax & # 179; + bx-5 is 7; when x = - 3, what is the value of the algebraic formula ax & # 179; + BX + 5?

When x = 3, the value of the algebraic formula ax & # 179; + bx-5 is 7; when x = - 3, what is the value of the algebraic formula ax & # 179; + BX + 5?

When x = 3
ax³+bx-5
=27a+3b-5=7
27a+3b=12
9a+b=4
When x = - 3
ax³+bx+5
=-27a-3b+5
=-3（9a+b）+5
=-3x4+5
=-7

It is known that when x = 1, the algebraic formula ax + B = 2, when x = 2, the algebraic formula ax + B = 1, find the value of the algebraic formula when x = 5

x=1,a+b=2,x=2,2a+b=1.a=-1,b=3,x=5,5*(-1)+3=-2

When x = 2, the value of AX + 3 is 5; when x = - 2, the value of the algebraic expression ax-3 is ()
A. -5B. 1C. -1D. 2

According to the meaning of the question, we get 2A + 3 = 5, the solution is a = 1, substituting a = 1 and x = - 2, we get ax-3 = - 2-3 = - 5