Any person desiring a change in assessment as provided in Section 27-35-143 shall make, in writing, an application in duplicate to the board of supervisors of the county where such assessment is made (or the tax assessor of the county may make such applications for him) on the forms prescribed, setting forth the grounds for the reduction, change, or cancellation claimed. At any meeting, either regular, special, or adjourned, the board of supervisors may hear and determine the matter and shall require such evidence as, in its opinion, is necessary to substantiate the application. If the board approves the application it shall adopt an order setting forth its conclusions, which order shall be dealt with as hereinafter provided. The state tax commission shall prescribe and furnish the forms necessary for complying with the provisions of this section.