问题
解答题
先化简,再求值.
(1)当a=1.3时,求5a+8a-8的值.
(2)当x=5时,求16x×2+23的值.
答案
(1)当a=1.3时,
5a+8a-8,
=13a-8,
=13×1.3-8,
=16.9-8,
=8.9;
(2)当x=5时,
16x×2+23,
=32x+23,
=32×5+23,
=160+23,
=183.
先化简,再求值.
(1)当a=1.3时,求5a+8a-8的值.
(2)当x=5时,求16x×2+23的值.
(1)当a=1.3时,
5a+8a-8,
=13a-8,
=13×1.3-8,
=16.9-8,
=8.9;
(2)当x=5时,
16x×2+23,
=32x+23,
=32×5+23,
=160+23,
=183.